William Harmong Lamar (born December 11, 1859 – February 10, 1928) was an American lawyer.^[1]

The son of Dr. William Harmong Lamar, and Ann Maria Lamar, née Glenn, William Harmong Lamar was born in Auburn, Alabama, on December 11, 1859; he had five siblings.

He married Virginia Longstreet on June 21, 1887. They had four children: Mrs. Virginia Longstreet Matthews, née Lamar (1889–1977); Mrs. Augusta Glenn "Gussie" Lytle, née Lamar (1891–1973); Lucius Quintus Cinncinatus Lamar (1892–1954); and William Harmong Lamar III (1897–1970).^[1] William H. Lamar IV is, As of 2025 pastor of the Metropolitan African Methodist Episcopal Church in Washington DC.

He received a Bachelor of Arts (A.B.) from Alabama Polytechnic in 1881, a Bachelor of Laws (LL.B.) from Georgetown University in 1884, and a Master of Laws (LL.M.) in 1885, also from Georgetown.^[1]

During the Spanish–American War, he served as a captain in the US Volunteer Signal Corps and in public relations campaigns for the war.^[1]

He began his practice of law in Washington, D.C. and Rockville, Maryland shortly after graduation and was elected to the Maryland House of Delegates in 1894 as a Democrat.^[1]

He served as an assistant attorney for the United States Department of Justice from 1906 to 1913.^[1]

Following the election of Woodrow Wilson, a fellow Democrat, as President, he was made assistant attorney-general and Solicitor of the Post Office Department (1913-1921),^[1][2] because of which he was targeted by anarchists for assassination in the 1919 United States anarchist bombings.^[3]

He left office after the election of Warren Harding, a Republican, as President in 1921 and served in private practice with his son Lucius until his death in 1928.^[4]

He was a member of the American Bar Association, the Maryland Bar Association, Alpha Tau Omega and Phi Delta Phi. He was also a Methodist.^[1]

He died at the Walter Reed General Hospital (WRGH), Washington, D.C., on February 10, 1928,^[5] and was buried at the Arlington National Cemetery.

• Marquis, A.N. (ed,) (1928), "William Harmong Lamar", p.1248 in Who's Who in America: Vol.15, Chicago, IL: The A.N. Marquis Company.
• Cramp, A.J. (ed.) (1921). Nostrums and Quackery: Volume II. Chicago, IL: American Medical Association.
• Materer, Timothy (1991). The Selected Letters of Ezra Pound to John Quinn: 1915–1924. Duke University Press. ISBN 978-0-8223-8290-4.
• Witemeyer, Hugh (1996). Pound/Williams: Selected Letters of Ezra Pound and William Carlos Williams. New Directions Publishing. ISBN 978-0-8112-1301-1.