Beauregard entered the Civil War as the Confederacy’s first brigadier general and was placed in command of the defenses of Charleston, South Carolina. In this role he ordered the first shots of the Civil War during the bombardment of Fort Sumter (April 12-14, 1861). After his success in taking Fort Sumter, Beauregard served as second-in-command to General Joseph E. Johnston during the Confederate victory at the First Battle of Bull Run in July 1861. He was then promoted to full general—a rank achieved by only seven other Confederate officers during the Civil War. During this time Beauregard began the first of many quarrels with the Confederate administration over field tactics, particularly over what he saw as Confederate President Jefferson Davis’ failure to adequately pursue the routed Union Army after the First Battle of Bull Run.
Beauregard next served in the war’s Western Theater under General Albert Sidney Johnston. At the Battle of Shiloh in April 1862, Beauregard assumed command of Confederate forces after Johnston was killed. Early Confederate attacks had placed Union General Ulysses S. Grant’s forces on their heels, but Beauregard made the controversial decision to delay a second offensive until the following day. This allowed the Union Army to gain reinforcements and then launch a counterattack that drove the Confederates from the field. The battle resulted in over 23,000 total casualties, and Beauregard’s army was pursued to Corinth, Mississippi, where a month-long siege ensued. Faced with a Union force twice the size of his own, Beauregard elected to withdraw to Tupelo, Mississippi, in May 1862.
Beauregard’s decision to abandon Corinth—a vital rail center—further contributed to his poor relationship with Jefferson Davis, and he was subsequently relieved from duty while on sick leave and replaced by General Braxton Bragg. Beauregard was then placed in command of the coastal defenses of South Carolina, Georgia and Florida, and supervised the defense of Charleston throughout 1863 and early 1864. During this time Beauregard implemented many innovative defensive strategies—including the use of mines and submarines—and managed to hold Charleston against repeated attacks by Union navy vessels and ironclads.
In April 1864 Beauregard was transferred again and tasked with leading the Department of North Carolina and Southern Virginia. In this capacity he was successful in withstanding an offensive by a much larger Union force during the Second Battle of Petersburg in June 1864. His actions forced the Union Army into what would become a 10-month siege of the city and halted an offensive that would have likely resulted in the capture of the Confederate capital of Richmond.
In October 1864 Beauregard was given a departmental command that encompassed several states in the Deep South and included jurisdiction over General John Bell Hood’s Army of the Tennessee. Beauregard was limited to an advisory role and was ultimately unsuccessful in halting Union General William T. Sherman’s famous “March to the Sea” during the Savannah Campaign in November and December 1864. Beauregard was eventually replaced in his command by General Joseph E. Johnston, and the two later surrendered to Sherman in North Carolina in April 1865.