A graduate of USMA, West Point, NY in 1838, Beauregard won two brevets in Mexico with Winfield Scott and was wounded at both Churubusco and Chapultepec. In the interwar years he was engaged in clearing the Mississippi River of obstructions. On 20 February 1861, he resigned his captaincy in the engineers at West Point and offered his services to the South. He was placed in charge of the South Carolina troops in Charleston Harbor, and won the nearly bloodless victory at Fort Sumter.
Who Was Who in America, Chicago, 1963, p. 48; Johnson, Rossiter (ed.), The Twentieth Century Biographical Dictionary of Notable Americans, Boston, 1904, vol. 1, p. 241; Cullum Memorial Edition, Register of Graduates and former cadets, United States Military Academy, West Point, 1980, No. 942.