1818–93, Confederate general, b. St. Bernard parish, La., grad. West Point, 1838. As engineer on the staff of Winfield Scott in the Mexican War, he figured prominently in the taking of Mexico City. He later did engineering work in Louisiana, and for five days in Jan., 1861, he was superintendent of West Point. Beauregard, resigning from the army in February, was soon made a Confederate brigadier general and was given command at Charleston, where he ordered the firing on Fort Sumter. Assuming command of the army in NE Virginia (June), he was second in command to J. E. Johnston at the first battle of Bull Run (July 16, 1861) and was promoted to full general.
He was sent to the West in 1862 and succeeded to the command of the Army of Tennessee upon the death of A. S. Johnston at the battle of Shiloh. Ill health and friction with Jefferson Davis, whom he had criticized after Bull Run, resulted in his removal from command. After a rest he was charged with the defense of the South Carolina and Georgia coast, which he ably held against Union attacks, particularly those on Charleston in 1863. In May, 1864, Beauregard reinforced Lee in Virginia. He defeated B. F. Butler at Drewry’s Bluff and held Petersburg against Grant until Lee arrived. In the closing months of the war he was in the Carolinas with J. E. Johnston. After the war Beauregard was a railroad president, manager of the Louisiana state lottery, and for many years adjutant general of that state. His superior engineering abilities overshadowed his deficiencies as a field commander.