Principal Officers and Chiefs of Mission, by Name: M

Note: Career Foreign Service appointees are asterisked.

• Raymond Edwin Mabus (1948–)
  • Ambassador Extraordinary and Plenipotentiary, Saudi Arabia (1994–1996)
• *Douglas MacArthur II (1909–1997)
  • Counselor (1953–1956)
  • Ambassador Extraordinary and Plenipotentiary, Japan (1956–1961)
  • Ambassador Extraordinary and Plenipotentiary, Belgium (1961–1965)
  • Career Ambassador (1964)
  • Assistant Secretary of State for Legislative Affairs (1965–1967)
  • Ambassador Extraordinary and Plenipotentiary, Austria (1967–1969)
  • Ambassador Extraordinary and Plenipotentiary, Iran (1969–1972)
• Nathan William MacChesney (1878–1954)
  • Envoy Extraordinary and Minister Plenipotentiary, Canada (Not commissioned; nomination not confirmed by the Senate.)
• *Howard P. Mace (1916–)
  • Ambassador Extraordinary and Plenipotentiary, Sierra Leone (Not commissioned; nomination not confirmed by the Senate.)
• *David Lyle Mack (1940–)
  • Principal Officer, Iraq (1978)
  • Ambassador Extraordinary and Plenipotentiary, United Arab Emirates (1986–1989)
• Earle I. Mack (1935–)
  • Ambassador Extraordinary and Plenipotentiary, Finland (2004–2005)
• *James F. Mack (1941–)
  • Chargé d’Affaires, Ecuador (1993)
  • Ambassador Extraordinary and Plenipotentiary, Guyana (1997–2000)
• Harold Orville MacKenzie (1886–1980)
  • Envoy Extraordinary and Minister Plenipotentiary, Thailand (1927–1930)
• *Jesse MacKenzie MacKnight (1910–1990)
  • Chargé d’Affaires ad interim, Togo ()
• Archibald MacLeish (1892–1982)
  • Assistant Secretary of State for Public Affairs (1944–1945)
• *Joseph E. Macmanus (1953–)
  • Representative of the U.S.A. to the Vienna Office of the United Nations (Vienna) (2012–2014)
  • Representative of the U.S.A. to the International Atomic Energy Agency (Vienna) (2012–2014)
  • Executive Secretary (2014–2017)
  • Envoy Extraordinary and Minister Plenipotentiary, Colombia (Nominated onNovember 29, 2017; nomination returned by the Senate on January 4, 2019.)
• *John Van Antwerp MacMurray (1881–1960)
  • Assistant Secretary of State (1924–1925)
  • Envoy Extraordinary and Minister Plenipotentiary, China (1925–1929)
  • Envoy Extraordinary and Minister Plenipotentiary, Estonia (1933–1936)
  • Envoy Extraordinary and Minister Plenipotentiary, Latvia (1933–1936)
  • Envoy Extraordinary and Minister Plenipotentiary, Lithuania (1933–1936)
  • Ambassador Extraordinary and Plenipotentiary, Turkey (1936–1941)
• Hanford MacNider (1889–1968)
  • Envoy Extraordinary and Minister Plenipotentiary, Canada (1930–1932)
• William Butts Macomber Jr. (1921–2003)
  • Assistant Secretary of State for Legislative Affairs (1957–1961)
  • Ambassador Extraordinary and Plenipotentiary, Jordan (1961–1963)
  • Assistant Secretary of State for Legislative Affairs (1967–1969)
  • Deputy Under Secretary of State for Management (1969–1973)
  • Ambassador Extraordinary and Plenipotentiary, Turkey (1973–1977)
• Charles MacVeagh (1860–1931)
  • Ambassador Extraordinary and Plenipotentiary, Japan (1925–1928)
• Isaac Wayne MacVeagh (1833–1917)
  • Minister Resident, Turkey (1870–1871)
  • Ambassador Extraordinary and Plenipotentiary, Italy (1893–1897)
• Lincoln MacVeagh (1890–1972)
  • Envoy Extraordinary and Minister Plenipotentiary, Greece (1933–1941)
  • Envoy Extraordinary and Minister Plenipotentiary, Iceland (1941–1942)
  • Envoy Extraordinary and Minister Plenipotentiary, South Africa (1942–1943)
  • Ambassador Extraordinary and Plenipotentiary, Greece (1943–1947)
  • Ambassador Extraordinary and Plenipotentiary, Yugoslavia (1943–1944)
  • Ambassador Extraordinary and Plenipotentiary, Portugal (1948–1952)
  • Ambassador Extraordinary and Plenipotentiary, Spain (1952–1953)
• William Percy Maddox (1901–1972)
  • Director of the Foreign Service Institute (1947–1949)
• James Madison (1751–1836)
  • Secretary of State (1801–1809)
• Kirsten D. Madison (?–)
  • Assistant Secretary of State for International Narcotics and Law Enforcement Affairs (2018)
• *Frank Eusebio Maestrone (1922–2007)
  • Ambassador Extraordinary and Plenipotentiary, Kuwait (1976–1979)
• Rufus Magee (1845–1929)
  • Minister Resident, Sweden (1885–1889)
  • Envoy Extraordinary and Minister Plenipotentiary, Sweden (1888–1889)
• Samuel Abbot Maginnis (1885–1941)
  • Envoy Extraordinary and Minister Plenipotentiary, Bolivia (1919–1921)
• Charles Edward Magoon (1861–1920)
  • Envoy Extraordinary and Minister Plenipotentiary, Panama (1905–1906)
• *Alexander Richardson Magruder (1883–1973)
  • Chargé d’Affaires pro tempore, Finland (1922)
• William W. Maguire (1908–)
  • Ambassador Extraordinary and Plenipotentiary, Guyana (Not commissioned; nomination not acted upon by the Senate.)
• Rowland Blennerhassett Mahany (1864–1937)
  • Envoy Extraordinary and Minister Plenipotentiary, Ecuador (1892–1893)
• *Patricia Mahoney (?–)
  • Ambassador Extraordinary and Plenipotentiary, Benin (2019)
• William Patrick Mahoney Jr. (1916–)
  • Ambassador Extraordinary and Plenipotentiary, Ghana (1962–1965)
• William Somers Mailliard (1917–1992)
  • Permanent Representative of the U.S.A. to the Organization of American States (Washington) (1974–1977)
• Theodore C. Maino (1913–1997)
  • Ambassador Extraordinary and Plenipotentiary, Botswana (1982–1985)
• *John F. Maisto (1938–)
  • Ambassador Extraordinary and Plenipotentiary, Nicaragua (1993–1996)
  • Ambassador Extraordinary and Plenipotentiary, Venezuela (1997–2000)
  • Permanent Representative of the U.S.A. to the Organization of American States (Washington) (2003–2006)
• *Dayton S. Mak (1917–)
  • Chargé d’Affaires, Kuwait (1962)
• *Deborah Ruth Malac (1955–)
  • Ambassador Extraordinary and Plenipotentiary, Liberia (2012–2015)
  • Ambassador Extraordinary and Plenipotentiary, Uganda (2015–2020)
• *Michael E. Malinowski (1948–)
  • Chargé d’Affaires ad interim, Philippines (2001)
  • Ambassador Extraordinary and Plenipotentiary, Nepal (2001–2004)
• Tomasz P. Malinowski (1965–)
  • Assistant Secretary of State for Democracy, Human Rights, and Labor (2014–2017)
• *Lester DeWitt Mallory (1904–1994)
  • Ambassador Extraordinary and Plenipotentiary, Jordan (1953–1958)
  • Ambassador Extraordinary and Plenipotentiary, Guatemala (1958–1959)
• *Eileen A. Malloy (1954–)
  • Ambassador Extraordinary and Plenipotentiary, Kyrgyzstan (1994–1997)
• Dudley Field Malone (1882–1950)
  • Third Assistant Secretary of State (1913)
• James L. Malone (1931–1996)
  • Assistant Secretary of State for Oceans and International Environmental and Scientific Affairs (1981–1985)
  • Ambassador Extraordinary and Plenipotentiary, Belize (Nomination of January 22, 1986, withdrawn on October 14, 1986.)
  • Ambassador at Large (Not commissioned; nomination of Mar 8, 1982, was withdrawn before the Senate acted on it. Nominated as Ambassador at Large and Special Representative of the President for the Law of the Sea Conference, and Chief of Delegation.)
• *F. Stephen Malott (1949–)
  • Chargé d’Affaires ad interim, Seychelles (1994)
• *John Raymond Malott (1946–)
  • Ambassador Extraordinary and Plenipotentiary, Malaysia (1995–1998)
• *Noah Bryson Mamet (1969–)
  • Ambassador Extraordinary and Plenipotentiary, Argentina (2014–2017)
• Charles Taylor Manatt (1936–2011)
  • Ambassador Extraordinary and Plenipotentiary, Dominican Republic (1999–2001)
• *David John Stanger Manbey (1919–1994)
  • Chargé d’Affaires ad interim, Rwanda ()
• Doug Manchester (?–)
• Robert A. Mandell (1947–)
  • Ambassador Extraordinary and Plenipotentiary, Luxembourg (2011–2015)
• *Jean Elizabeth Manes (1970–)
  • Ambassador Extraordinary and Plenipotentiary, El Salvador (2016–2019)
• George Earl Maney (1826–1901)
  • Minister Resident, Colombia (1881–1882)
  • Minister Resident/Consul General, Bolivia (1882–1883)
  • Minister Resident, Paraguay (1889–1891)
  • Minister Resident, Uruguay (1889–1890)
  • Envoy Extraordinary and Minister Plenipotentiary, Paraguay (1890–1894)
  • Envoy Extraordinary and Minister Plenipotentiary, Uruguay (1890–1894)
  • Minister Resident, Ecuador (Not commissioned; nomination withdrawn before the Senate acted upon it.)
• *Melvin Lawrence Manfull (1919–2000)
  • Ambassador Extraordinary and Plenipotentiary, Central African Republic (1970–1972)
  • Ambassador Extraordinary and Plenipotentiary, Liberia (1972–1975)
• *Philip Wallace Manhard (1921–1998)
  • Ambassador Extraordinary and Plenipotentiary, Mauritius (1974–1976)
• Ambrose Dudley Mann (1801–1889)
  • Assistant Secretary of State (1853–1855)
• Fredric Rand Mann (1903–1987)
  • Ambassador Extraordinary and Plenipotentiary, Barbados (1967–1969)
• *Steven Robert Mann (1951–)
  • Chargé d’Affaires ad interim, Armenia (1992)
  • Ambassador Extraordinary and Plenipotentiary, Turkmenistan (1998–2001)
  • Chargé d’Affaires ad interim, Mongolia ()
• *Thomas Clifton Mann (1912–1999)
  • Ambassador Extraordinary and Plenipotentiary, El Salvador (1955–1957)
  • Assistant Secretary of State for Western Hemisphere Affairs (1957–1961)
  • Assistant Secretary of State for Economic, Energy, and Business Affairs (1957–1960)
  • Ambassador Extraordinary and Plenipotentiary, Mexico (1961–1963)
  • Assistant Secretary of State for Western Hemisphere Affairs (1963–1965)
  • Under Secretary for Economic Growth, Energy, and the Environment (1965–1966)
• Robert Joseph Manning (1919–2012)
  • Assistant Secretary of State for Public Affairs (1962–1964)
• Thomas Courtland Manning (1825–1887)
  • Envoy Extraordinary and Minister Plenipotentiary, Mexico (1886–1887)
• John Kenneth Mansfield (1951–)
  • Inspector General of Foreign Assistance (1962–1969)
• Michael Joseph Mansfield (1903–2001)
  • Ambassador Extraordinary and Plenipotentiary, Japan (1977–1988)
• Warren Demian Manshel (1924–1990)
  • Ambassador Extraordinary and Plenipotentiary, Denmark (1978–1981)
• Theodore Marburg (1862–1946)
  • Envoy Extraordinary and Minister Plenipotentiary, Belgium (1912–1914)
• *Scot Alan Marciel (1958–)
  • Representative of the U.S.A. to the Association of Southeast Asian Nations (Jakarta) (2008–2010)
  • Ambassador Extraordinary and Plenipotentiary, Indonesia (2010–2013)
  • Ambassador Extraordinary and Plenipotentiary, Burma (2016–2020)
• Jeffrey A. Marcus (1945–)
  • Ambassador Extraordinary and Plenipotentiary, Belgium (Nomination not acted upon by the Senate.)
• William Learned Marcy (1786–1857)
  • Secretary of State (1853–1857)
• *Michael W. Marine (1947–)
  • Chargé d’Affaires ad interim, Fiji (1995)
  • Chargé d’Affaires ad interim, Kiribati (1995)
  • Chargé d’Affaires ad interim, Tonga (1995)
  • Chargé d’Affaires ad interim, Tuvalu (1995)
  • Ambassador Extraordinary and Plenipotentiary, Vietnam (2004–2007)
• *David Everett Mark (1923–2005)
  • Ambassador Extraordinary and Plenipotentiary, Burundi (1974–1977)
• Leopold Markbreit (1842–1909)
  • Minister Resident, Bolivia (1869–1873)
• *Edward Marks (1934–)
  • Ambassador Extraordinary and Plenipotentiary, Cape Verde (1977–1980)
  • Ambassador Extraordinary and Plenipotentiary, Guinea-Bissau (1977–1980)
• Lana J. Marks (?–)
  • Ambassador Extraordinary and Plenipotentiary, South Africa (2019)
• Leonard Harold Marks (1916–2006)
  • Director of the U.S. Information Agency (1965–1968)
• John Leake Marling (1825–1856)
  • Minister Resident, Guatemala (1854–1856)
  • Envoy Extraordinary and Minister Plenipotentiary, Guatemala (Nominated on February 25, 1856; nomination withdrawn before the Senate acted upon it.)
• *R. Niels Marquardt (1954–)
  • Ambassador Extraordinary and Plenipotentiary, Equatorial Guinea (2004–2006)
  • Ambassador Extraordinary and Plenipotentiary, Cameroon (2004–2007)
  • Ambassador Extraordinary and Plenipotentiary, Comoros (2007–2010)
  • Ambassador Extraordinary and Plenipotentiary, Madagascar (2007–2010)
• Victor Marrero (1941–)
  • Permanent Representative of the U.S.A. to the Organization of American States (Washington) (1998–1999)
• George Perkins Marsh (1801–1882)
  • Minister Resident, Turkey (1849–1853)
  • Envoy Extraordinary and Minister Plenipotentiary, Italy (1861–1882)
• *William H. Marsh (1931–2017)
  • U.S. Representative to the United Nations Agencies for Food and Agriculture (Rome) (1992–1994)
• Anthony Dryden Marshall (1924–2014)
  • Ambassador Extraordinary and Plenipotentiary, Madagascar (1969–1971)
  • Ambassador Extraordinary and Plenipotentiary, Trinidad and Tobago (1972–1973)
  • Ambassador Extraordinary and Plenipotentiary, Kenya (1973–1977)
  • Ambassador Extraordinary and Plenipotentiary, Seychelles (1976–1977)
• Capricia Penavic Marshall (1964–)
  • Chief of Protocol (2009–2013)
• George Catlett Marshall (1880–1959)
  • Secretary of State (1947–1949)
• Humphrey Marshall (1812–1872)
  • Commissioner, China (1852–1854)
• John Marshall (1755–1835)
  • Secretary of State (1800–1801)
  • Secretary of State ad interim (1801)
• *Charles E. Marthinsen (1931–)
  • Ambassador Extraordinary and Plenipotentiary, Qatar (1980–1983)
• *Cheryl Ann Martin (1946–)
  • Chargé d’Affaires ad interim, Micronesia, Federated States of (1999)
• *Edwin McCammon Martin (1908–2002)
  • Assistant Secretary of State for Economic, Energy, and Business Affairs (1960–1962)
  • Assistant Secretary of State for Western Hemisphere Affairs (1962–1964)
  • Ambassador Extraordinary and Plenipotentiary, Argentina (1964–1968)
  • Career Ambassador (1969)
• *Edwin Webb Martin (1917–1991)
  • Ambassador Extraordinary and Plenipotentiary, Burma (1971–1973)
• *Graham Anderson Martin (1912–1990)
  • Representative of the U.S.A. to the European Office of the United Nations (Geneva) (1960–1962)
  • Ambassador Extraordinary and Plenipotentiary, Thailand (1963–1967)
  • Ambassador Extraordinary and Plenipotentiary, Italy (1969–1973)
  • Ambassador Extraordinary and Plenipotentiary, South Vietnam (1973–1975)
• Jacob L. Martin (?–1848)
  • Chief Clerk (1840–1841)
  • Secretary of State ad interim (1841)
  • Chargé d’Affaires, Holy See (1848)
• John Bartlow Martin (1915–1987)
  • Ambassador Extraordinary and Plenipotentiary, Dominican Republic (1962–1963)
• John Funk Martin Jr. (1889–1971)
  • Chargé d’Affaires ad interim, Costa Rica ()
• Anne Clark Martindell (1914–2008)
  • Ambassador Extraordinary and Plenipotentiary, Samoa (1979–1981)
  • Ambassador Extraordinary and Plenipotentiary, New Zealand (1979–1981)
• *Carmen Maria Martinez (1950–)
  • Chargé d’Affaires, Burma (2005)
  • Ambassador Extraordinary and Plenipotentiary, Zambia (2005–2008)
• *Elizabeth Lee Martinez (1958–)
  • Chargé d’Affaires ad interim, Jamaica (2015)
• Vilma S. Martinez (1943–)
  • Ambassador Extraordinary and Plenipotentiary, Argentina (2009–2013)
• Josiah Marvel Jr. (1904–1955)
  • Envoy Extraordinary and Minister Plenipotentiary, Denmark (1946–1947)
  • Ambassador Extraordinary and Plenipotentiary, Denmark (1947–1949)
• George T. Marye (1857–1933)
  • Ambassador Extraordinary and Plenipotentiary, Russia (1914–1916)
• *Barbara C. Maslak (?–)
  • Chargé d’Affaires ad interim, Guinea-Bissau (1986)
• James W. Mason (?–)
  • Minister Resident/Consul General, Liberia (1870)
• John Young Mason (1799–1859)
  • Envoy Extraordinary and Minister Plenipotentiary, France (1853–1859)
• Edward Masso (?–)
  • Envoy Extraordinary and Minister Plenipotentiary, Estonia (Nomination of September 5, 2017 withdrawn on May 24, 2018.)
• *Edward E. Masters (1924–2014)
  • Ambassador Extraordinary and Plenipotentiary, Bangladesh (1976–1977)
  • Ambassador Extraordinary and Plenipotentiary, Indonesia (1977–1981)
• *Richard Cavins Matheron (1927–)
  • Ambassador Extraordinary and Plenipotentiary, Swaziland (1979–1982)
• *Elbert George Mathews (1910–1977)
  • Ambassador Extraordinary and Plenipotentiary, Liberia (1959–1962)
  • Ambassador Extraordinary and Plenipotentiary, Nigeria (1964–1969)
• *Gail Dennise Thomas Mathieu (1951–)
  • Ambassador Extraordinary and Plenipotentiary, Niger (2002–2005)
  • Ambassador Extraordinary and Plenipotentiary, Namibia (2007–2010)
• *Jack Foust Matlock Jr. (1929–)
  • Ambassador Extraordinary and Plenipotentiary, Czechoslovakia (1981–1983)
  • Ambassador Extraordinary and Plenipotentiary, Russia (1987–1991)
• Roderick Nathaniel Matson (1871–1933)
  • Envoy Extraordinary and Minister Plenipotentiary, Greece (Not commissioned; nomination withdrawn before the Senate acted upon it.)
• Francis Patrick Matthews (1887–1952)
  • Ambassador Extraordinary and Plenipotentiary, Ireland (1951–1952)
• *Gary L. Matthews (1938–)
  • Ambassador Extraordinary and Plenipotentiary, Malta (1985–1987)
• *Harrison Freeman Matthews (1899–1986)
  • Ambassador Extraordinary and Plenipotentiary, Sweden (1947–1950)
  • Envoy Extraordinary and Minister Plenipotentiary, Sweden (1947)
  • Ambassador Extraordinary and Plenipotentiary, Netherlands (1953–1957)
  • Secretary of State ad interim (1953)
  • Career Ambassador (1956)
  • Ambassador Extraordinary and Plenipotentiary, Austria (1957–1962)
  • Chargé d’Affaires ad interim, Spain ()
• *Matthew J. Matthews (?–)
  • Ambassador Extraordinary and Plenipotentiary, Brunei (2019–2020)
• Mack F. Mattingly (1931–)
  • Ambassador Extraordinary and Plenipotentiary, Seychelles (1992–1993)
• Dabney Herndon Maury (1822–1900)
  • Envoy Extraordinary and Minister Plenipotentiary, Colombia (1886–1889)
• Carlyle Edward Maw (1903–1987)
  • Legal Adviser (1973–1974)
  • Under Secretary of State for Arms Control and International Security Affairs (1974–1976)
• Virgil Maxcy (1785–1844)
  • Chargé d’Affaires, Belgium (1837–1842)
• *Robert Morgan Maxim (1940–)
  • Chargé d’Affaires ad interim, Malawi (1981)
• *Ernest de Wael Mayer (1903–1968)
  • Chargé d’Affaires ad interim, Belgium ()
• *Ferdinand Lathrop Mayer (1887–1986)
  • Envoy Extraordinary and Minister Plenipotentiary, Haiti (1937–1940)
• Horace Maynard (1814–1882)
  • Minister Resident, Turkey (1875–1880)
• Charles William Maynes (1938–2007)
  • Assistant Secretary of State for International Organization Affairs (1977–1980)
• Marquita Moseley Maytag (1925–)
  • Ambassador Extraordinary and Plenipotentiary, Nepal (1976–1977)
• *Louis Mazel (1951–)
  • Chargé d’Affaires, Eritrea (2016)
• *Marilyn McAfee (1940–)
  • Ambassador Extraordinary and Plenipotentiary, Guatemala (1993–1996)
• Robert Breckinridge McAfee (1784–1849)
  • Chargé d’Affaires, Colombia (1833–1837)
• Eugene J. McAllister (1952–)
  • Assistant Secretary of State for Economic, Energy, and Business Affairs (1988–1992)
• *John E. McAteer (1939–)
  • Chargé d’Affaires ad interim, Djibouti (1988)
• *Eugene Vincent McAuliffe (1918–2000)
  • Ambassador Extraordinary and Plenipotentiary, Hungary (1975–1976)
• James McBride (1802–1875)
  • Minister Resident, Hawaii (1863–1866)
• *Robert Henry McBride (1918–1983)
  • Ambassador Extraordinary and Plenipotentiary, Congo (Kinshasa) (1967–1969)
  • Ambassador Extraordinary and Plenipotentiary, Mexico (1969–1974)
• Richard Lee McCall Jr. (1942–)
  • Assistant Secretary of State for International Organization Affairs (1980–1981)
• *Marshall Fletcher McCallie (1945–)
  • Ambassador Extraordinary and Plenipotentiary, Namibia (1993–1996)
• Robert D. McCallum (1946–)
  • Ambassador Extraordinary and Plenipotentiary, Australia (2006–2009)
• William E. McCann (1930–2002)
  • Ambassador Extraordinary and Plenipotentiary, Ireland (Not commissioned; nomination of March 17, 1981, not acted upon by the Senate.)
• Carl Wesley McCardle (1904–1972)
  • Assistant Secretary of State for Public Affairs (1953–1957)
• Kyle McCarter (?–)
  • Ambassador Extraordinary and Plenipotentiary, Kenya (2019)
• *Deborah Ann McCarthy (1955–)
  • Ambassador Extraordinary and Plenipotentiary, Lithuania (2013–2016)
• Ellen E. McCarthy (?–)
  • Assistant Secretary of State for Intelligence and Research (2019)
• Frank McCarthy (1912–1986)
  • Assistant Secretary of State for Administration (1945)
• *John Thomas McCarthy (1939–)
  • Ambassador Extraordinary and Plenipotentiary, Lebanon (1988–1990)
  • Ambassador Extraordinary and Plenipotentiary, Tunisia (1991–1994)
• Daniel Smith McCauley (?–1852)
  • Agent/Consul General, Egypt (1848–1852)
• Susan Rasinski McCaw (1962–)
  • Ambassador Extraordinary and Plenipotentiary, Austria (2005–2007)
• George Brinton McClellan (1826–1885)
  • Envoy Extraordinary and Minister Plenipotentiary, United Kingdom (Not commissioned; nomination rejected by the Senate.)
• *Roswell Dunlop McClelland (1914–1995)
  • Chargé d’Affaires ad interim, Senegal (1960)
  • Ambassador Extraordinary and Plenipotentiary, Niger (1970–1973)
• *Lee McClenny (1961–)
  • Chargé d’Affaires, Venezuela (2017)
  • Ambassador Extraordinary and Plenipotentiary, Paraguay (2018–2020)
• John Alexander McClernand (1812–1900)
  • Envoy Extraordinary and Minister Plenipotentiary, Mexico (Not commissioned; nomination twice rejected by the Senate.)
• *David W. McClintock (?–)
  • Principal Officer, Yemen (1972)
• *Robert Mills McClintock (1909–1976)
  • Ambassador Extraordinary and Plenipotentiary, Cambodia (1954–1956)
  • Ambassador Extraordinary and Plenipotentiary, Lebanon (1957–1961)
  • Ambassador Extraordinary and Plenipotentiary, Argentina (1962–1964)
  • Ambassador Extraordinary and Plenipotentiary, Venezuela (1970–1975)
• Matthew Henry McCloskey Jr. (1893–1973)
  • Ambassador Extraordinary and Plenipotentiary, Ireland (1962–1964)
• *Robert James McCloskey (1922–1996)
  • Ambassador Extraordinary and Plenipotentiary, Cyprus (1973–1974)
  • Ambassador at Large (1973–1975)
  • Assistant Secretary of State for Legislative Affairs (1975–1976)
  • Ambassador Extraordinary and Plenipotentiary, Netherlands (1976–1978)
  • Ambassador Extraordinary and Plenipotentiary, Greece (1978–1981)
• Alexander Keith McClung (1812–1855)
  • Chargé d’Affaires, Bolivia (1849–1851)
• *Walter Patrick McConaughy Jr. (1908–2000)
  • Ambassador Extraordinary and Plenipotentiary, Burma (1957–1959)
  • Ambassador Extraordinary and Plenipotentiary, Korea (1959–1961)
  • Assistant Secretary of State for East Asian and Pacific Affairs (1961)
  • Ambassador Extraordinary and Plenipotentiary, Pakistan (1962–1966)
  • Ambassador Extraordinary and Plenipotentiary, China (1966–1974)
• *Donald J. McConnell (1939–)
  • Ambassador Extraordinary and Plenipotentiary, Burkina Faso (1993–1996)
  • Ambassador Extraordinary and Plenipotentiary, Eritrea (2001–2004)
• Edward Moody McCook (1833–1909)
  • Minister Resident, Hawaii (1866–1868)
• Richard T. McCormack (1941–)
  • Assistant Secretary of State for Economic, Energy, and Business Affairs (1983–1985)
  • Permanent Representative of the U.S.A. to the Organization of American States (Washington) (1985–1989)
  • Under Secretary for Economic Growth, Energy, and the Environment (1989–1991)
• *Sean McCormack (1964–)
  • Assistant Secretary of State for Public Affairs (2005–2009)
• Robert Sanderson McCormick (1849–1919)
  • Envoy Extraordinary and Minister Plenipotentiary, Austria (1901–1902)
  • Ambassador Extraordinary and Plenipotentiary, Austria (1902)
  • Ambassador Extraordinary and Plenipotentiary, Russia (1902–1905)
  • Ambassador Extraordinary and Plenipotentiary, France (1905–1907)
• William Paul McCormick (1939–)
  • Ambassador Extraordinary and Plenipotentiary, Samoa (2005–2008)
  • Ambassador Extraordinary and Plenipotentiary, New Zealand (2005–2008)
• Jamie D. McCourt (?–)
  • Ambassador Extraordinary and Plenipotentiary, France (2017)
  • Ambassador Extraordinary and Plenipotentiary, Monaco (2017)
  • Ambassador Extraordinary and Plenipotentiary, Belgium (Nominated June 26, 2017, withdrawn on August 2, 2017.)
• William D. McCoy (1853–1893)
  • Minister Resident/Consul General, Liberia (1892–1893)
• Fenton Reuben McCreery (1866–1940)
  • Minister Resident/Consul General, Dominican Republic (1907–1909)
  • Envoy Extraordinary and Minister Plenipotentiary, Honduras (1909–1911)
• *Terence Patrick McCulley (1957–)
  • Ambassador Extraordinary and Plenipotentiary, Mali (2005–2008)
  • Ambassador Extraordinary and Plenipotentiary, Nigeria (2010–2013)
  • Ambassador Extraordinary and Plenipotentiary, Côte d’Ivoire (2013–2016)
• Charles Johnson McCurdy (1797–1891)
  • Chargé d’Affaires, Austria (1850–1852)
• Michael James McDermott (1894–1955)
  • Ambassador Extraordinary and Plenipotentiary, El Salvador (1953–1954)
• Alexander McDonald (1827–1897)
  • Minister Resident/Consul General, Iran (1893–1897)
  • Envoy Extraordinary and Minister Plenipotentiary, Iran (1893)
• *Jackson C. McDonald (1956–)
  • Ambassador Extraordinary and Plenipotentiary, The Gambia (2001–2004)
  • Ambassador Extraordinary and Plenipotentiary, Guinea (2004–2007)
• James Grover McDonald (1886–1964)
  • Ambassador Extraordinary and Plenipotentiary, Israel (1949–1950)
• Tom McDonald (1954–)
  • Ambassador Extraordinary and Plenipotentiary, Zimbabwe (1997–2000)
• William Wallace McDowell (1867–1934)
  • Envoy Extraordinary and Minister Plenipotentiary, Ireland (1933)
  • Envoy Extraordinary and Minister Plenipotentiary, Ireland (1934)
• *Nancy E. McEldowney (1958–)
  • Ambassador Extraordinary and Plenipotentiary, Bulgaria (2008–2009)
  • Director of the Foreign Service Institute (2013–2017)
• *Douglas L. McElhaney (1947–)
  • Ambassador Extraordinary and Plenipotentiary, Bosnia and Herzegovina (2004–2007)
• *Thomas Watkins McElhiney (1919–1998)
  • Ambassador Extraordinary and Plenipotentiary, Ghana (1968–1971)
  • Inspector General of the Department of State and the Foreign Service (1971–1973)
  • Ambassador Extraordinary and Plenipotentiary, Ethiopia (1974)
• Bonnie McElveen-Hunter (1950–)
  • Ambassador Extraordinary and Plenipotentiary, Finland (2001–2003)
• *Jack Kirkham McFall (1905–1990)
  • Assistant Secretary of State for Legislative Affairs (1949–1952)
  • Envoy Extraordinary and Minister Plenipotentiary, Finland (1952–1954)
  • Ambassador Extraordinary and Plenipotentiary, Finland (1954–1955)
• Kathleen Troia Mcfarland (?–)
  • Ambassador Extraordinary and Plenipotentiary, Singapore (Nominated June 15, 2017 and renominated January 8, 2018. Nomination withdrawn by the president on February 5, 2018.)
• *Stephen George McFarland (1954–)
  • Ambassador Extraordinary and Plenipotentiary, Guatemala (2008–2011)
• Robert Carl McFarlane (1937–)
  • Counselor (1981–1982)
• Michael Anthony McFaul (1963–)
  • Ambassador Extraordinary and Plenipotentiary, Russia (2012–2014)
• *C. Steven McGann (1951–)
  • Ambassador Extraordinary and Plenipotentiary, Fiji (2008–2011)
  • Ambassador Extraordinary and Plenipotentiary, Kiribati (2008–2011)
  • Ambassador Extraordinary and Plenipotentiary, Tonga (2008–2011)
  • Ambassador Extraordinary and Plenipotentiary, Nauru (2008–2011)
  • Ambassador Extraordinary and Plenipotentiary, Tuvalu (2008–2011)
• Gale McGee (1915–1992)
  • Permanent Representative of the U.S.A. to the Organization of American States (Washington) (1977–1981)
• *James D. McGee (1949–)
  • Ambassador Extraordinary and Plenipotentiary, Swaziland (2002–2004)
  • Ambassador Extraordinary and Plenipotentiary, Madagascar (2004–2007)
  • Ambassador Extraordinary and Plenipotentiary, Comoros (2006)
  • Ambassador Extraordinary and Plenipotentiary, Zimbabwe (2007–2009)
• George Crews McGhee (1912–2005)
  • Assistant Secretary of State for Near Eastern Affairs (1949–1951)
  • Ambassador Extraordinary and Plenipotentiary, Turkey (1951–1953)
  • Under Secretary of State for Political Affairs (1961–1963)
  • Director of Policy Planning (1961)
  • Counselor (1961)
  • Ambassador Extraordinary and Plenipotentiary, Germany (1963–1968)
  • Ambassador at Large (1968–1969)
• John McGinnis Jr. (?–)
  • Minister Resident, Sweden (1866)
• Preston Buford McGoodwin (1880–1945)
  • Envoy Extraordinary and Minister Plenipotentiary, Venezuela (1913–1921)
• George Stanley McGovern (1922–2012)
  • U.S. Representative to the United Nations Agencies for Food and Agriculture (Rome) (1998–2001)
• Gerald S. McGowan (1946–)
  • Ambassador Extraordinary and Plenipotentiary, Portugal (1997–2001)
• *Kevin Joseph McGuire (1943–)
  • Ambassador Extraordinary and Plenipotentiary, Namibia (2001–2004)
• *Ralph Jack McGuire (1920–1996)
  • Ambassador Extraordinary and Plenipotentiary, Mali (1973–1976)
• *Roger A. McGuire (1943–2005)
  • Chargé d’Affaires ad interim, Namibia (1990)
  • Ambassador Extraordinary and Plenipotentiary, Guinea-Bissau (1992–1995)
• Brett H. McGurk (1973–)
  • Ambassador Extraordinary and Plenipotentiary, Iraq (Nomination of March 27, 2012, withdrawn on June 18, 2012.)
• *Joseph F. McGurk (1892–1962)
  • Ambassador Extraordinary and Plenipotentiary, Dominican Republic (1945)
  • Ambassador Extraordinary and Plenipotentiary, Uruguay (1946–1947)
• Judith A. McHale (1947–)
  • Under Secretary of State for Public Diplomacy and Public Affairs (2009–2011)
• Donald F. McHenry (1936–)
  • Representative of the U.S.A. to the United Nations (1979–1981)
• *R. James McHugh (1947–)
  • Chargé d’Affaires ad interim, Antigua and Barbuda (1989)
  • Chargé d’Affaires ad interim, Saint Kitts and Nevis (1989)
• *Robinson McIlvaine (1913–2001)
  • Ambassador Extraordinary and Plenipotentiary, Benin (1961–1964)
  • Ambassador Extraordinary and Plenipotentiary, Guinea (1966–1969)
  • Ambassador Extraordinary and Plenipotentiary, Kenya (1969–1973)
• Dempster McIntosh (1896–1984)
  • Ambassador Extraordinary and Plenipotentiary, Uruguay (1953–1956)
  • Ambassador Extraordinary and Plenipotentiary, Venezuela (1956–1957)
  • Ambassador Extraordinary and Plenipotentiary, Colombia (1959–1961)
• *John W. McIntyre (?–)
  • Chargé d’Affaires ad interim, Trinidad and Tobago (2018)
• David McKean (1956–)
  • Director of Policy Planning (2013–2016)
  • Ambassador Extraordinary and Plenipotentiary, Luxembourg (2016–2017)
• *Alan R. McKee (1943–)
  • Ambassador Extraordinary and Plenipotentiary, Swaziland (1996–1999)
• *Erin E. McKee (?–)
  • Ambassador Extraordinary and Plenipotentiary, Solomon Islands (2019)
  • Ambassador Extraordinary and Plenipotentiary, Papua New Guinea (2019)
  • Ambassador Extraordinary and Plenipotentiary, Vanuatu (2019)
• James Andrew McKenzie (1840–1904)
  • Envoy Extraordinary and Minister Plenipotentiary, Peru (1893–1897)
• *John Alexander McKesson III (1922–2002)
  • Ambassador Extraordinary and Plenipotentiary, Gabon (1970–1975)
• *Brunson McKinley (1943–)
  • Ambassador Extraordinary and Plenipotentiary, Haiti (1986–1989)
• *Peter Michael McKinley (1954–)
  • Chargé d’Affaires ad interim, Mozambique (1997)
  • Ambassador Extraordinary and Plenipotentiary, Peru (2007–2010)
  • Ambassador Extraordinary and Plenipotentiary, Colombia (2010–2013)
  • Ambassador Extraordinary and Plenipotentiary, Afghanistan (2014–2016)
  • Ambassador Extraordinary and Plenipotentiary, Brazil (2016–2018)
• Frank Edward McKinney (1904–1974)
  • Ambassador Extraordinary and Plenipotentiary, Spain (1968)
• Luther Franklin McKinney (1841–1922)
  • Envoy Extraordinary and Minister Plenipotentiary, Colombia (1893–1896)
• Robert Moody McKinney (1910–2001)
  • Representative of the U.S.A. to the International Atomic Energy Agency (Vienna) (1957–1958)
  • Ambassador Extraordinary and Plenipotentiary, Switzerland (1961–1963)
• *Elizabeth Davenport McKune (1947–)
  • Ambassador Extraordinary and Plenipotentiary, Qatar (1998–2001)
• Louis McLane (1786–1857)
  • Envoy Extraordinary and Minister Plenipotentiary, United Kingdom (1829–1831)
  • Secretary of State (1833–1834)
  • Envoy Extraordinary and Minister Plenipotentiary, United Kingdom (1845–1849)
• Robert Milligan McLane (1815–1898)
  • Commissioner, China (1853–1854)
  • Envoy Extraordinary and Minister Plenipotentiary, Mexico (1859–1860)
  • Envoy Extraordinary and Minister Plenipotentiary, France (1885–1889)
• Stanley Louis McLelland (1945–)
  • Ambassador Extraordinary and Plenipotentiary, Jamaica (1997–2001)
• Robert Walter Scott McLeod (1914–1961)
  • Assistant Secretary of State for Consular Affairs (1953–1957)
  • Ambassador Extraordinary and Plenipotentiary, Ireland (1957–1961)
• Martin Thomas McMahon (1838–1906)
  • Minister Resident, Paraguay (1868–1869)
• *Clayton E. McManaway Jr. (1933–2010)
  • Director of the Office of Management Policy (1976–1977)
  • Ambassador Extraordinary and Plenipotentiary, Haiti (1983–1986)
• Benton McMillin (1845–1933)
  • Envoy Extraordinary and Minister Plenipotentiary, Peru (1913–1919)
  • Envoy Extraordinary and Minister Plenipotentiary, Guatemala (1919–1921)
• *Margaret K. McMillion (1951–)
  • Ambassador Extraordinary and Plenipotentiary, Rwanda (2001–2004)
• Douglas W. McMinn (1947–)
  • Assistant Secretary of State for Economic, Energy, and Business Affairs (1985–1987)
• *Christopher J. McMullen (1952–)
  • Ambassador Extraordinary and Plenipotentiary, Angola (2010–2013)
• Edward T. McMullen Jr. (?–)
  • Ambassador Extraordinary and Plenipotentiary, Switzerland (2017)
  • Ambassador Extraordinary and Plenipotentiary, Liechtenstein (2017)
• *Ronald Keith McMullen (1955–)
  • Chargé d’Affaires ad interim, Fiji (2002)
  • Chargé d’Affaires ad interim, Tonga (2002)
  • Chargé d’Affaires ad interim, Nauru (2002)
  • Chargé d’Affaires ad interim, Tuvalu (2002)
  • Ambassador Extraordinary and Plenipotentiary, Eritrea (2007–2010)
• Claudia A. McMurray (1958–)
  • Assistant Secretary of State for Oceans and International Environmental and Scientific Affairs (2006–2009)
• *Francis Terry McNamara (1927–)
  • Ambassador Extraordinary and Plenipotentiary, Gabon (1981–1984)
  • Ambassador Extraordinary and Plenipotentiary, Sao Tome and Principe (1981–1984)
  • Ambassador Extraordinary and Plenipotentiary, Cape Verde (1989–1992)
• *Thomas Edmund McNamara (1940–)
  • Ambassador Extraordinary and Plenipotentiary, Colombia (1988–1991)
  • Assistant Secretary of State for Politico-Military Affairs (1994–1998)
• *Francis J. McNeil (1932–)
  • Ambassador Extraordinary and Plenipotentiary, Costa Rica (1980–1983)
• Paul Vories McNutt (1891–1955)
  • Ambassador Extraordinary and Plenipotentiary, Philippines (1946–1947)
• Harry Cummings McPherson Jr. (1929–2012)
  • Assistant Secretary of State for Educational and Cultural Affairs (1964–1965)
• Melville Peter McPherson (1940–)
  • Administrator of the Agency for International Development (1981–1987)
• *John Morgan McSweeney (1916–1979)
  • Envoy Extraordinary and Minister Plenipotentiary, Bulgaria (1966–1967)
  • Ambassador Extraordinary and Plenipotentiary, Bulgaria (1967–1970)
• *Edmund McWilliams (1947–)
  • Chargé d’Affaires ad interim, Kyrgyzstan ()
  • Chargé d’Affaires ad interim, Tajikistan ()
• Richard Kidder Meade (1803–1862)
  • Chargé d’Affaires, Italy (1853)
  • Envoy Extraordinary and Minister Plenipotentiary, Brazil (1857–1861)
• Samuel Medary (1801–1864)
  • Envoy Extraordinary and Minister Plenipotentiary, Chile (1853)
• *Roger A. Meece (1949–)
  • Ambassador Extraordinary and Plenipotentiary, Malawi (2000–2003)
  • Ambassador Extraordinary and Plenipotentiary, Congo (Kinshasa) (2004–2007)
• *Francis Joseph Meehan (1924–)
  • Ambassador Extraordinary and Plenipotentiary, Czechoslovakia (1979–1980)
  • Ambassador Extraordinary and Plenipotentiary, Poland (1980–1983)
  • Ambassador Extraordinary and Plenipotentiary, German Democratic Republic (1985–1988)
• Leonard Carpenter Meeker (1916–2014)
  • Legal Adviser (1965–1969)
  • Ambassador Extraordinary and Plenipotentiary, Romania (1969–1973)
• *John Gordon Mein (1913–1968)
  • Ambassador Extraordinary and Plenipotentiary, Guatemala (1965–1968)
• Thomas Patrick Melady (1927–2014)
  • Ambassador Extraordinary and Plenipotentiary, Burundi (1969–1972)
  • Ambassador Extraordinary and Plenipotentiary, Uganda (1972–1973)
  • Ambassador Extraordinary and Plenipotentiary, Holy See (1989–1993)
• Andrew William Mellon (1855–1937)
  • Ambassador Extraordinary and Plenipotentiary, United Kingdom (1932–1933)
• *Harry Roberts Melone Jr. (1928–2009)
  • Ambassador Extraordinary and Plenipotentiary, Rwanda (1979–1982)
• *Francis Edward Meloy Jr. (1917–1976)
  • Ambassador Extraordinary and Plenipotentiary, Dominican Republic (1969–1973)
  • Ambassador Extraordinary and Plenipotentiary, Guatemala (1973–1976)
  • Ambassador Extraordinary and Plenipotentiary, Lebanon (1976)
• *Joseph H. Melrose Jr. (1944–2014)
  • Ambassador Extraordinary and Plenipotentiary, Sierra Leone (1998–2001)
• *Richard Huntington Melton (1935–)
  • Ambassador Extraordinary and Plenipotentiary, Nicaragua (1988)
  • Ambassador Extraordinary and Plenipotentiary, Brazil (1989–1993)
• *James Desmond Melville Jr. (1957–)
  • Ambassador Extraordinary and Plenipotentiary, Estonia (2015–2018)
• *Larry L. Memmott (1960–)
  • Chargé d’Affaires ad interim, Bolivia (2014)
• *Joseph Abraham Mendenhall (1920–)
  • Ambassador Extraordinary and Plenipotentiary, Madagascar (1972–1975)
• *John K. Menzies (1948–)
  • Ambassador Extraordinary and Plenipotentiary, Bosnia and Herzegovina (1995–1996)
• *Livingston Tallmadge Merchant (1903–1976)
  • Assistant Secretary of State for European and Eurasian Affairs (1953–1956)
  • Assistant Secretary of State for European and Eurasian Affairs (1953–1959)
  • Ambassador Extraordinary and Plenipotentiary, Canada (1956–1958)
  • Under Secretary of State for Political Affairs (1959–1961)
  • Deputy Under Secretary of State for Political Affairs (1959)
  • Career Ambassador (1960)
  • Ambassador Extraordinary and Plenipotentiary, Canada (1961–1962)
  • Secretary of State ad interim (1961)
• Van Santvoord Merle-Smith (1889–1943)
  • Third Assistant Secretary of State (1920–1921)
• *George Robert Merrell (1898–1962)
  • Chargé d’Affaires ad interim, Haiti (1926)
  • Envoy Extraordinary and Minister Plenipotentiary, Ethiopia (1947–1949)
  • Ambassador Extraordinary and Plenipotentiary, Ethiopia (1949–1951)
  • Ambassador Extraordinary and Plenipotentiary, Afghanistan (1951–1952)
  • Chargé d’Affaires ad interim, India ()
• *Gordon Phelps Merriam (1899–1999)
  • Chargé d’Affaires ad interim, Iran (1937)
• Ayres Phillips Merrill (1825–1883)
  • Minister Resident, Belgium (1876–1877)
• *David Nathan Merrill (1943–)
  • Ambassador Extraordinary and Plenipotentiary, Bangladesh (1994–1997)
• George W. Merrill (1837–1914)
  • Minister Resident, Hawaii (1885–1889)
• *Heather Merritt (?–)
  • Chargé d’Affaires ad interim, Angola (2014)
• William Lawrence Merry (1835–1911)
  • Envoy Extraordinary and Minister Plenipotentiary, El Salvador (1897–1907)
  • Envoy Extraordinary and Minister Plenipotentiary, Costa Rica (1897–1907)
  • Envoy Extraordinary and Minister Plenipotentiary, Nicaragua (1897–1907)
  • Envoy Extraordinary and Minister Plenipotentiary, Costa Rica (1907–1908)
  • Envoy Extraordinary and Minister Plenipotentiary, Nicaragua (1907–1908)
  • Envoy Extraordinary and Minister Plenipotentiary, Costa Rica (1908–1911)
• *Kenneth H. Merten (1961–)
  • Ambassador Extraordinary and Plenipotentiary, Haiti (2009–2012)
  • Ambassador Extraordinary and Plenipotentiary, Croatia (2012–2015)
• *George Strausser Messersmith (1883–1960)
  • Envoy Extraordinary and Minister Plenipotentiary, Austria (1934–1937)
  • Envoy Extraordinary and Minister Plenipotentiary, Uruguay (1934)
  • Assistant Secretary of State (1937–1940)
  • Ambassador Extraordinary and Plenipotentiary, Cuba (1940–1942)
  • Ambassador Extraordinary and Plenipotentiary, Mexico (1941–1946)
  • Ambassador Extraordinary and Plenipotentiary, Argentina (1946–1947)
• Perle (Pearl) Reid Skirvin Mesta (1889–1975)
  • Envoy Extraordinary and Minister Plenipotentiary, Luxembourg (1949–1953)
• *Michael D. Metelits (1942–)
  • Ambassador Extraordinary and Plenipotentiary, Cape Verde (1999–2002)
• *Armin Henry Meyer (1914–2006)
  • Ambassador Extraordinary and Plenipotentiary, Lebanon (1961–1965)
  • Ambassador Extraordinary and Plenipotentiary, Iran (1965–1969)
  • Ambassador Extraordinary and Plenipotentiary, Japan (1969–1972)
• Charles Appleton Meyer (1918–1996)
  • Assistant Secretary of State for Western Hemisphere Affairs (1969–1973)
• Francis Gerald Meyer (1913–1995)
  • Assistant Secretary of State for Administration (1969–1971)
• George von Lengerke Meyer (1858–1918)
  • Ambassador Extraordinary and Plenipotentiary, Italy (1900–1905)
  • Ambassador Extraordinary and Plenipotentiary, Russia (1905–1907)
• *Marilyn Ann Meyers (1942–)
  • Chargé d’Affaires ad interim, Burma (1996)
• *Manuel P. Micaller (?–)
  • Chargé d’Affaires ad interim, Mongolia (2019)
• *Michael W. Michalak (1946–)
  • Ambassador Extraordinary and Plenipotentiary, Vietnam (2007–2011)
• James H. Michel (1939–)
  • Ambassador Extraordinary and Plenipotentiary, Guatemala (1987–1989)
• John William Middendorf II (1924–)
  • Ambassador Extraordinary and Plenipotentiary, Netherlands (1969–1973)
  • Permanent Representative of the U.S.A. to the Organization of American States (Washington) (1981–1985)
  • Representative of the U.S.A. to the European Union, with the rank and status of Ambassador Extraordinary and Plenipotentiary (1985–1987)
• Henry Middleton (1770–1846)
  • Envoy Extraordinary and Minister Plenipotentiary, Russia (1820–1830)
• *William B. Milam (1936–)
  • Ambassador Extraordinary and Plenipotentiary, Bangladesh (1990–1993)
  • Ambassador Extraordinary and Plenipotentiary, Pakistan (1998–2001)
  • Chargé d’Affaires ad interim, Liberia (1999)
• *Richard Monroe Miles (1937–)
  • Ambassador Extraordinary and Plenipotentiary, Azerbaijan (1992–1993)
  • Ambassador Extraordinary and Plenipotentiary, Bulgaria (1999–2002)
  • Chargé d’Affaires ad interim, Socialist Federal Republic of Yugoslavia (1999)
  • Ambassador Extraordinary and Plenipotentiary, Georgia (2002–2005)
• *Stephanie Miley (?–)
  • Chargé d’Affaires ad interim, Morocco (2019)
• *Elisabeth I. Millard (1954–)
  • Ambassador Extraordinary and Plenipotentiary, Tajikistan (2015–2017)
• H.A. Millen (?–)
  • Minister Resident, Hawaii (Not commissioned; nomination withdrawn before the Senate acted upon it.)
• David Charles Miller Jr. (1942–)
  • Ambassador Extraordinary and Plenipotentiary, Tanzania (1981–1984)
  • Ambassador Extraordinary and Plenipotentiary, Zimbabwe (1984–1986)
• *Earl Robert Miller (1958–)
  • Ambassador Extraordinary and Plenipotentiary, Botswana (2014–2018)
  • Ambassador Extraordinary and Plenipotentiary, Bangladesh (2018)
• Edward Godfrey Miller Jr. (1911–1968)
  • Assistant Secretary of State for Western Hemisphere Affairs (1949–1952)
• Horace H. Miller (?–)
  • Chargé d’Affaires, Bolivia (1852–1854)
• John Rippin Miller (1938–)
  • Ambassador at Large (2004–2006)
• Lloyd Ivan Miller Jr. (1924–1990)
  • Ambassador Extraordinary and Plenipotentiary, Trinidad and Tobago (1973–1975)
• *Raymond Clendenin Miller (1895–1963)
  • Inspector General of the Department of State and the Foreign Service (1957–1960)
• *Robert Hopkins Miller (1927–)
  • Ambassador Extraordinary and Plenipotentiary, Malaysia (1977–1980)
  • Ambassador Extraordinary and Plenipotentiary, Côte d’Ivoire (1983–1986)
• *Thomas Joel Miller (1949–)
  • Ambassador Extraordinary and Plenipotentiary, Bosnia and Herzegovina (1999–2001)
  • Ambassador Extraordinary and Plenipotentiary, Greece (2001–2004)
• William Miller (1770–1825)
  • Chargé d’Affaires, Guatemala (1825)
• *William Green Miller (1931–)
  • Ambassador Extraordinary and Plenipotentiary, Ukraine (1993–1998)
• James L. Millette (1956–)
  • Comptroller and Director of the Bureau of Global Financial Services (2012–2014)
• *Jeffrey Millington (1944–)
  • Director, Angola (1992)
  • Chargé d’Affaires, Sudan (2003)
• Cheryl D. Mills (1965–)
  • Counselor (2009–2013)
• *Hawthorne Quinn Mills (1928–)
  • Chargé d’Affaires ad interim, Afghanistan (1982)
• *Richard M. Mills Jr. (1959–)
  • Ambassador Extraordinary and Plenipotentiary, Armenia (2015–2018)
• *Sheldon Tibbetts Mills (1904–1988)
  • Ambassador Extraordinary and Plenipotentiary, Ecuador (1954–1956)
  • Ambassador Extraordinary and Plenipotentiary, Afghanistan (1956–1959)
  • Ambassador Extraordinary and Plenipotentiary, Jordan (1959–1961)
• *Gillian Arlette Milovanovic (1949–)
  • Ambassador Extraordinary and Plenipotentiary, Macedonia (2005–2008)
  • Ambassador Extraordinary and Plenipotentiary, Mali (2008–2011)
• *Robert Graham Miner (1911–1990)
  • Ambassador Extraordinary and Plenipotentiary, Trinidad and Tobago (1962–1967)
  • Ambassador Extraordinary and Plenipotentiary, Sierra Leone (1967–1971)
• Patsy Takemoto Mink (1927–2002)
  • Assistant Secretary of State for Oceans and International Environmental and Scientific Affairs (1977–1978)
• *Harold Bronk Minor (1902–1984)
  • Envoy Extraordinary and Minister Plenipotentiary, Lebanon (1951–1952)
  • Ambassador Extraordinary and Plenipotentiary, Lebanon (1952–1953)
• *John Russell Minter (1893–1970)
  • Chargé d’Affaires ad interim, Australia (Minter was serving as Chargé d’Affaires ad interim when Legation Canberra was raised to Embassy status, July 19, 1946.)
• *Mark C. Minton (1944–)
  • Ambassador Extraordinary and Plenipotentiary, Mongolia (2006–2009)
• A. Wess Mitchell (1977–)
  • Assistant Secretary of State for European and Eurasian Affairs (2017–2019)
• Charles Edward Mitchell (1870–)
  • Minister Resident/Consul General, Liberia (1930)
  • Envoy Extraordinary and Minister Plenipotentiary, Liberia (1931)
• Derek J. Mitchell (1964–)
  • Ambassador Extraordinary and Plenipotentiary, Burma (2012–2016)
• *William Coleman Mithoefer Jr. (1931–)
  • Chargé d’Affaires ad interim, Guinea (1987)
• Lansing Bond Mizner (1825–1893)
  • Envoy Extraordinary and Minister Plenipotentiary, El Salvador (1889–1890)
  • Envoy Extraordinary and Minister Plenipotentiary, Costa Rica (1889–1890)
  • Envoy Extraordinary and Minister Plenipotentiary, Honduras (1889)
  • Envoy Extraordinary and Minister Plenipotentiary, Guatemala (1889–1890)
  • Envoy Extraordinary and Minister Plenipotentiary, Nicaragua (1889–1890)
• Douglas Maxwell Moffat (1881–1956)
  • Ambassador Extraordinary and Plenipotentiary, Australia (1956)
• *Jay P. Moffat (1932–)
  • Ambassador Extraordinary and Plenipotentiary, Chad (1983–1985)
• *Jay Pierrepont Moffat (1896–1943)
  • Envoy Extraordinary and Minister Plenipotentiary, Canada (1940–1943)
  • Envoy Extraordinary and Minister Plenipotentiary, Luxembourg (1941–1943)
• *William A. Moffitt (1944–)
  • Chargé d’Affaires ad interim, Malta (1994)
• Kevin E. Moley (1946–)
  • Representative of the U.S.A. to the European Office of the United Nations (Geneva) (2001–2006)
  • Assistant Secretary of State for International Organization Affairs (2018)
• Raymond Charles Moley (1886–1975)
  • Assistant Secretary of State (1933)
• *Patricia Newton Moller (1944–)
  • Ambassador Extraordinary and Plenipotentiary, Burundi (2006–2009)
  • Ambassador Extraordinary and Plenipotentiary, Guinea (2009–2012)
• Walter F. Mondale (1928–)
  • Ambassador Extraordinary and Plenipotentiary, Japan (1993–1996)
• Joseph N. Mondello (?–)
  • Ambassador Extraordinary and Plenipotentiary, Trinidad and Tobago (2018)
• *John Cameron Monjo (1931–)
  • Chargé d’Affaires ad interim, Indonesia (1983)
  • Ambassador Extraordinary and Plenipotentiary, Malaysia (1987–1989)
  • Ambassador Extraordinary and Plenipotentiary, Indonesia (1989–1992)
  • Ambassador Extraordinary and Plenipotentiary, Pakistan (1992–1995)
• *Gerald J. Monroe (1933–)
  • U.S. Representative to the United Nations Agencies for Food and Agriculture (Rome) (1988–1992)
• James Monroe (1758–1831)
  • Minister Plenipotentiary, France (1794–1796)
  • Minister Plenipotentiary, United Kingdom (1803–1807)
  • Secretary of State (1811–1814)
  • Secretary of State ad interim (1814–1815)
  • Secretary of State (1815–1817)
• *William T. Monroe (1950–)
  • Ambassador Extraordinary and Plenipotentiary, Bahrain (2004–2007)
• George Cranwell Montgomery (1944–)
  • Ambassador Extraordinary and Plenipotentiary, Oman (1985–1989)
• Hugh Montgomery (1923–2017)
  • Assistant Secretary of State for Intelligence and Research (1981–1985)
• John Flournoy Montgomery (1878–1954)
  • Envoy Extraordinary and Minister Plenipotentiary, Hungary (1933–1941)
• *William Dale Montgomery (1945–)
  • Ambassador Extraordinary and Plenipotentiary, Bulgaria (1993–1996)
  • Ambassador Extraordinary and Plenipotentiary, Croatia (1997–2000)
  • Ambassador Extraordinary and Plenipotentiary, Serbia (2001–2004)
• *Patrick S. Moon (1950–)
  • Ambassador Extraordinary and Plenipotentiary, Bosnia and Herzegovina (2010–2013)
• Daniel Francis Mooney (1865–1930)
  • Envoy Extraordinary and Minister Plenipotentiary, Paraguay (1914–1921)
• Thomas Moonlight (1833–1899)
  • Envoy Extraordinary and Minister Plenipotentiary, Bolivia (1894–1898)
• Alexander C. Moore (?–)
  • Minister Resident/Consul General, Thailand (1890)
• Alexander Pollock Moore (1867–1930)
  • Ambassador Extraordinary and Plenipotentiary, Spain (1923–1925)
  • Ambassador Extraordinary and Plenipotentiary, Peru (1928–1929)
  • Ambassador Extraordinary and Plenipotentiary, Poland (1930)
• *Barbara C. Moore (1952–2010)
  • Ambassador Extraordinary and Plenipotentiary, Nicaragua (2002–2005)
• *Charles Robert Moore (1915–1992)
  • Ambassador Extraordinary and Plenipotentiary, Mali (1965–1968)
  • Ambassador Extraordinary and Plenipotentiary, Equatorial Guinea (1972–1975)
  • Ambassador Extraordinary and Plenipotentiary, Cameroon (1972–1975)
• Frederick Randolph Moore (1857–1943)
  • Minister Resident/Consul General, Liberia (1913)
• *George Curtis Moore (1925–1973)
  • Principal Officer, Sudan (1972)
  • Chargé d’Affaires ad interim, Sudan (1972)
• *Jenifer H. Moore (?–)
  • Chargé d’Affaires, Belarus (2018–2020)
• Jerry Alexander Moore Jr. (1918–)
  • Ambassador Extraordinary and Plenipotentiary, Lesotho (Nomination of July 11, 1989, not acted upon by the Senate.)
• John Bassett Moore (1860–1947)
  • Third Assistant Secretary of State (1886–1891)
  • Assistant Secretary of State (1898)
  • Counselor (1913–1914)
• John Denis Joseph Moore (1910–1988)
  • Ambassador Extraordinary and Plenipotentiary, Ireland (1969–1975)
• Jonathan Moore (1932–2017)
  • Ambassador at Large (1986–1989)
  • Assistant Secretary of State for Population, Refugees, and Migration Affairs (1987–1989)
• *Jonathan Michael Moore (1966–)
  • Chargé d’Affaires ad interim, Belarus (2009)
• Powell Allen Moore (1938–)
  • Assistant Secretary of State for Legislative Affairs (1982–1983)
• Richard Anthony Moore (1914–1995)
  • Ambassador Extraordinary and Plenipotentiary, Ireland (1989–1992)
• Robert Walton Moore (1859–1941)
  • Assistant Secretary of State (1933–1937)
  • Counselor (1937–1941)
• *Roderick W. Moore (1964–)
  • Ambassador Extraordinary and Plenipotentiary, Montenegro (2007–2010)
• Thomas Patrick Moore (1797–1853)
  • Envoy Extraordinary and Minister Plenipotentiary, Colombia (1829–1833)
• *Kenneth Price Moorefield (1942–)
  • Ambassador Extraordinary and Plenipotentiary, Gabon (2002–2004)
  • Ambassador Extraordinary and Plenipotentiary, Sao Tome and Principe (2002–2004)
• *George Edward Moose (1944–)
  • Ambassador Extraordinary and Plenipotentiary, Benin (1983–1986)
  • Director of the Office of Management Policy (1987–1988)
  • Ambassador Extraordinary and Plenipotentiary, Senegal (1988–1991)
  • Assistant Secretary of State for African Affairs (1993–1997)
  • Representative of the U.S.A. to the European Office of the United Nations (Geneva) (1997–2001)
  • Career Ambassador (2002)
• *James Sayle Moose Jr. (1903–1989)
  • Minister Resident/Foreign Service officer, Saudi Arabia (1943–1944)
  • Envoy Extraordinary and Minister Plenipotentiary, Syria (1952)
  • Ambassador Extraordinary and Plenipotentiary, Syria (1952–1957)
  • Ambassador Extraordinary and Plenipotentiary, Sudan (1958–1962)
• Richard Menifee Moose (1932–2015)
  • Deputy Under Secretary of State for Management (1977)
  • Assistant Secretary of State for African Affairs (1977–1981)
  • Under Secretary of State for Management (1993–1996)
• Franklin E. Morales (1884–1962)
  • Envoy Extraordinary and Minister Plenipotentiary, Honduras (1921–1925)
• Hector E. Morales (1954–)
  • Permanent Representative of the U.S.A. to the Organization of American States (Washington) (2008–2009)
• Benjamin Moran (1820–1886)
  • Minister Resident, Portugal (1874–1876)
  • Chargé d’Affaires, Portugal (1876–1882)
  • Third Assistant Secretary of State (Not commissioned, although his nomination of Jun 22, 1874, had been confirmed by the Senate.)
• *James B. Moran (1924–1998)
  • Ambassador Extraordinary and Plenipotentiary, Seychelles (1987–1991)
• *James Bolard More (1907–)
  • Chargé d’Affaires ad interim, Cameroon ()
• John Motley Morehead (1870–1965)
  • Envoy Extraordinary and Minister Plenipotentiary, Sweden (1930–1933)
• Constance Albanese Morella (1931–)
  • Representative of the U.S.A. to the Organization for Economic Cooperation and Development (Paris) (2003–2005)
• Carlos Roberto Moreno (1948–)
  • Ambassador Extraordinary and Plenipotentiary, Belize (2014–2017)
• *Luis G. Moreno (1955–)
  • Ambassador Extraordinary and Plenipotentiary, Jamaica (2014–2017)
• Edwin Vernon Morgan (1865–1934)
  • Envoy Extraordinary and Minister Plenipotentiary, Cuba (1905–1910)
  • Envoy Extraordinary and Minister Plenipotentiary, Korea (1905)
  • Envoy Extraordinary and Minister Plenipotentiary, Paraguay (1909–1911)
  • Envoy Extraordinary and Minister Plenipotentiary, Uruguay (1909–1911)
  • Envoy Extraordinary and Minister Plenipotentiary, Portugal (1911–1912)
  • Ambassador Extraordinary and Plenipotentiary, Brazil (1912–1933)
• *George Allen Morgan (1905–1988)
  • Director of the Foreign Service Institute (1962–1965)
  • Ambassador Extraordinary and Plenipotentiary, Côte d’Ivoire (1965–1969)
• George Washington Morgan (1820–1893)
  • Minister Resident, Portugal (1858–1861)
• Philip Hicky Morgan (1825–1900)
  • Envoy Extraordinary and Minister Plenipotentiary, Mexico (1880–1885)
• Henry Morgenthau (1856–1946)
  • Ambassador Extraordinary and Plenipotentiary, Turkey (1913–1916)
  • Ambassador Extraordinary and Plenipotentiary, Mexico (Not commissioned; nomination not confirmed by the Senate.)
• *James F. Moriarty (1953–)
  • Ambassador Extraordinary and Plenipotentiary, Nepal (2004–2007)
  • Ambassador Extraordinary and Plenipotentiary, Bangladesh (2008–2011)
• Frederick Morley (1821–1889)
  • Agent/Consul General, Egypt (1876)
• Richard L. Morningstar (1945–)
  • Representative of the U.S.A. to the European Union, with the rank and status of Ambassador Extraordinary and Plenipotentiary (1999–2001)
  • Ambassador Extraordinary and Plenipotentiary, Azerbaijan (2012–2014)
• *Brewster Hilliard Morris (1909–1990)
  • Ambassador Extraordinary and Plenipotentiary, Chad (1963–1967)
• Dave Hennen Morris (1872–1944)
  • Ambassador Extraordinary and Plenipotentiary, Belgium (1933–1937)
  • Envoy Extraordinary and Minister Plenipotentiary, Luxembourg (1933–1937)
• Edward Joy Morris (1815–1881)
  • Chargé d’Affaires, Kingdom of the Two Sicilies (1850–1853)
  • Minister Resident, Turkey (1861–1870)
• Gouverneur Morris (1752–1816)
  • Minister Plenipotentiary, France (1792–1794)
• *Greta N. Morris (1947–)
  • Ambassador Extraordinary and Plenipotentiary, Marshall Islands (2003–2006)
• Ira Nelson Morris (1875–1942)
  • Envoy Extraordinary and Minister Plenipotentiary, Sweden (1914–1923)
• *Leland Burnette Morris (1886–1950)
  • Chargé d’Affaires ad interim, Germany (1941)
  • Envoy Extraordinary and Minister Plenipotentiary, Iceland (1942–1944)
  • Ambassador Extraordinary and Plenipotentiary, Iran (1944–1945)
• Roland Sletor Morris (1874–1945)
  • Ambassador Extraordinary and Plenipotentiary, Japan (1917–1920)
• deLesseps Story Morrison (1912–1964)
  • Permanent Representative of the U.S.A. to the Organization of American States (Washington) (1961–1963)
• Dwight Whitney Morrow (1873–1931)
  • Ambassador Extraordinary and Plenipotentiary, Mexico (1927–1930)
• John Howard Morrow (1910–2000)
  • Ambassador Extraordinary and Plenipotentiary, Guinea (1959–1961)
  • U.S. Permanent Representative to the United Nations Educational, Scientific and Cultural Organization (1961–1963)
• Levi Parsons Morton (1824–1920)
  • Envoy Extraordinary and Minister Plenipotentiary, France (1881–1885)
• Oliver Hazard Perry Throck Morton (1823–1877)
  • Envoy Extraordinary and Minister Plenipotentiary, United Kingdom (1870)
• Thruston Ballard Morton (1907–1982)
  • Assistant Secretary of State for Legislative Affairs (1953–1956)
• Emil Mosbacher Jr. (1922–1997)
  • Chief of Protocol (1969–1972)
• Georgette Mosbacher (?–)
  • Ambassador Extraordinary and Plenipotentiary, Poland (2018)
• Teodoro Moscoso (1910–1992)
  • Ambassador Extraordinary and Plenipotentiary, Venezuela (1961)
• Carol Moseley-Braun (1947–)
  • Ambassador Extraordinary and Plenipotentiary, Samoa (1999–2001)
  • Ambassador Extraordinary and Plenipotentiary, New Zealand (1999–2001)
• *Leo John Moser (1929–)
  • Chargé d’Affaires ad interim, Laos (1981)
• *William H. Moser (1964–)
  • Ambassador Extraordinary and Plenipotentiary, Moldova (2011–2015)
  • Ambassador Extraordinary and Plenipotentiary, Kazakhstan (2019)
• Alfred H. Moses (1929–)
  • Ambassador Extraordinary and Plenipotentiary, Romania (1994–1997)
• George Higgins Moses (1869–1944)
  • Envoy Extraordinary and Minister Plenipotentiary, Greece (1909–1912)
  • Envoy Extraordinary and Minister Plenipotentiary, Montenegro (1909–1912)
• *Leyla Moses-Ones (?–)
  • Chargé d’Affaires ad interim, Albania (2018)
• Ambler Holmes Moss Jr. (1937–)
  • Ambassador Extraordinary and Plenipotentiary, Panama (1978–1982)
• John Lothrop Motley (1814–1877)
  • Ambassador Extraordinary and Plenipotentiary, Austria (1861–1867)
  • Envoy Extraordinary and Minister Plenipotentiary, United Kingdom (1869–1870)
• Langhorne A. Motley (1938–)
  • Ambassador Extraordinary and Plenipotentiary, Brazil (1981–1983)
  • Assistant Secretary of State for Western Hemisphere Affairs (1983–1985)
• Thaddeus Phelps Mott (1831–1894)
  • Minister Resident, Costa Rica (Not commissioned; nomination withdrawn before the Senate acted upon it.)
• *Day Olin Mount (1940–)
  • Ambassador Extraordinary and Plenipotentiary, Iceland (1996–1999)
• Daniel Patrick Moynihan (1927–2003)
  • Ambassador Extraordinary and Plenipotentiary, India (1973–1975)
  • Representative of the U.S.A. to the United Nations (1975–1976)
• *Dan W. Mozena (1949–)
  • Ambassador Extraordinary and Plenipotentiary, Angola (2007–2010)
  • Ambassador Extraordinary and Plenipotentiary, Bangladesh (2011–2014)
• *Michael Mozur (1951–)
  • Chargé d’Affaires ad interim, Uzbekistan ()
• *George Mu (1943–)
  • Ambassador Extraordinary and Plenipotentiary, Côte d’Ivoire (1998–2001)
• *John Joseph Muccio (1900–1989)
  • Ambassador Extraordinary and Plenipotentiary, Korea (1949–1952)
  • Envoy Extraordinary and Minister Plenipotentiary, Iceland (1954–1955)
  • Ambassador Extraordinary and Plenipotentiary, Iceland (1955–1959)
  • Ambassador Extraordinary and Plenipotentiary, Guatemala (1959–1961)
• Henry Augustus Philip Muhlenberg (1782–1844)
  • Envoy Extraordinary and Minister Plenipotentiary, Austria (1838–1840)
• *Edward William Mulcahy (1921–2006)
  • Ambassador Extraordinary and Plenipotentiary, Chad (1972–1974)
  • Ambassador Extraordinary and Plenipotentiary, Tunisia (1976–1979)
• David Campbell Mulford (1937–)
  • Ambassador Extraordinary and Plenipotentiary, India (2003–2009)
• Douglas P. Mulholland (1929–)
  • Assistant Secretary of State for Intelligence and Research (1989–1993)
• *Stephen D. Mull (1958–)
  • Ambassador Extraordinary and Plenipotentiary, Lithuania (2003–2006)
  • Executive Secretary (2009–2012)
  • Ambassador Extraordinary and Plenipotentiary, Poland (2012–2015)
  • Career Ambassador (2016)
• Janet Gardner Mullins (1949–)
  • Assistant Secretary of State for Legislative Affairs (1989–1992)
• *Peter F. Mulrean (1959–)
  • Ambassador Extraordinary and Plenipotentiary, Haiti (2015–2017)
• *Dana Gardner Munro (1892–1990)
  • Envoy Extraordinary and Minister Plenipotentiary, Haiti (1930–1932)
• *Cameron Phelps Munter (1954–)
  • Ambassador Extraordinary and Plenipotentiary, Serbia (2007–2009)
  • Ambassador Extraordinary and Plenipotentiary, Pakistan (2010–2012)
• Henry Cruse Murphy (1810–1882)
  • Minister Resident, Netherlands (1857–1861)
• Philip D. Murphy (1957–)
  • Ambassador Extraordinary and Plenipotentiary, Germany (2009–2013)
• *Richard William Murphy (1929–)
  • Ambassador Extraordinary and Plenipotentiary, Mauritania (1971–1974)
  • Ambassador Extraordinary and Plenipotentiary, Syria (1974–1978)
  • Ambassador Extraordinary and Plenipotentiary, Philippines (1978–1981)
  • Ambassador Extraordinary and Plenipotentiary, Saudi Arabia (1981–1983)
  • Assistant Secretary of State for Near Eastern Affairs (1983–1989)
  • Career Ambassador (1985)
• *Robert Daniel Murphy (1894–1978)
  • Ambassador Extraordinary and Plenipotentiary, Belgium (1949–1952)
  • Ambassador Extraordinary and Plenipotentiary, Japan (1952–1953)
  • Deputy Under Secretary of State for Political Affairs (1953–1955)
  • Assistant Secretary of State for International Organization Affairs (1953)
  • Deputy Under Secretary of State for Political Affairs (1955–1959)
  • Career Ambassador (1956)
  • Under Secretary of State for Political Affairs (1959)
• *W. Patrick Murphy (?–)
  • Ambassador Extraordinary and Plenipotentiary, Cambodia (2019)
• William Sumter Murphy (1796–1844)
  • Chargé d’Affaires, Texas (1843–1844)
• *Christopher W. Murray (1953–)
  • Ambassador Extraordinary and Plenipotentiary, Congo (Brazzaville) (2010–2013)
• *Wallace Smith Murray (1887–1965)
  • Ambassador Extraordinary and Plenipotentiary, Iran (1945–1946)
• William Vans Murray (1760–1803)
  • Minister Resident, Netherlands (1797–1801)
  • Minister Plenipotentiary, France (Not commissioned; nomination superseded by a nomination of Murray and two others to serve on a joint commission.)
• Edward R. Murrow (1908–1965)
  • Director of the U.S. Information Agency (1961–1964)
• *Tulinabo Salama Mushingi (1956–)
  • Ambassador Extraordinary and Plenipotentiary, Burkina Faso (2013–2016)
  • Ambassador Extraordinary and Plenipotentiary, Guinea-Bissau (2017)
  • Ambassador Extraordinary and Plenipotentiary, Senegal (2017)
• Edmund Sixtus Muskie (1914–1996)
  • Secretary of State (1980–1981)
• *Joseph A. Mussomeli (1952–)
  • Ambassador Extraordinary and Plenipotentiary, Cambodia (2005–2008)
  • Ambassador Extraordinary and Plenipotentiary, Slovenia (2010–2015)
• *Herro K. Mustafa (?–)
  • Ambassador Extraordinary and Plenipotentiary, Bulgaria (2019)
• *Allan P. Mustard (1955–)
  • Ambassador Extraordinary and Plenipotentiary, Turkmenistan (2014–2019)
• *Marianne Matuzek Myles (1953–)
  • Ambassador Extraordinary and Plenipotentiary, Cape Verde (2008–2011)
• *Bismarck Myrick (1940–)
  • Ambassador Extraordinary and Plenipotentiary, Lesotho (1995–1998)
  • Ambassador Extraordinary and Plenipotentiary, Liberia (1999–2002)