Lyon, Leroy Springs was born on October 15, 1866 in Petersburg, Virginia, United States. Son of John and Margaret M. (Springs) Lyon.
Bachelor of Arts, Richmond College, 1886 (Doctor of Laws, 1919). Graduated from the United States Master of Arts, 1891, Coast Artillery School, Fort Monroe, Virginia, 1898, School of Submarine Defense, Fort Totten, New York, 1903.
Commissioned Second lieutenant 7th Cavalry, June 12, 1891. Promoted through grades to colonel May 15, 1917. Brigadier general N.A., August 5, 1917.
Major general N.A., April 12, 1918. A.d.c. to General Royal T. Frank, 1898-1899, serving at Chickamauga Park, Georgia, Anniston, Alabama, and headquarters Department of Gulf. With light battery and 2d Artillery, in Cuba, 1899-1900.
District artillery engineer, Fort Barrancas, Florida, 1903-1906. In P.I., 1906-1907, participating in expedition against hostile Moros. Served in Canal Zone.
1916-1917; at El Paso, Texas, August 1917. Commanded 65th Field Artillery Brigade, Camp Kearny, California, August 25, 1917-May 1918. Commanded 31st (Dixie) Division, Camp Wheeler, Georgia, and in France, May-November 1918, 90th Division, November-December 1918.
In France, September 29, 1918-May 13, 1919. Participated in Meuse-Argonne offensive, October 11-October 18, 1918. Commanded Camp Bowie, Texas, May-July 15, 1918.
Returned to regular rank of colonel Field Artillery, July 15, 1918, commanded Field Artillery Basic School, Camp Taylor, Kentucky, July 26, 1919—.