Modern reproduction of a photograph depicting General Ulysses S. Grant posed with his staff while campaigning in Virginia during the Civil War, 1864.
During the American Civil War, the Army of the Potomac was the North's primary army operating in the East. Organized in July 1861, this force confronted the Confederacy's Army of Northern Virginia throughout the conflict.
Despite having superior numbers, the Army of the Potomac suffered numerous defeats during the war's first years. The Battle of First Bull Run in 1861, the Peninsula Campaign and the Battle of Fredericksburg in 1862, and the Battle of Chancellorsville in 1863 were all Northern defeats. The Army of the Potomac did succeed in stopping the Army of Northern Virginia's invasions of the North at the Battle of Antietam in 1862 and the Battle of Gettysburg in 1863, but victories during the conflict's first three years were few for the Army of the Potomac.
One of the primary reasons for the lack of victories for the Army of the Potomac was the lack of a successful leader. Many historians have described the Army of the Potomac's leaders during the early years of the war as being lackluster and, in some cases, incompetent. The army's first commander was Ohioan General Irvin McDowell. Following the Union defeat at the Battle of First Bull Run, President Abraham Lincoln replaced McDowell with Ohioan General George McClellan. Known for his tremendous organizational skills, McClellan succeeded in creating a well-trained army. Unfortunately for the North, McClellan failed to decisively confront the South on the battlefield. In late 1862, General Ambrose Burnside replaced McClellan. The Army of Northern Virginia soundly defeated Burnside's army at the Battle of Fredericksburg in December 1862. Burnside, who was known for and gave his name to sideburns, was quickly replaced with General Joseph Hooker who was defeated at the Battle of Chancellorsville.
In June 1863, General George Meade became the commander of the Army of the Potomac. He took command of the army only a few days before the Battle of Gettysburg. Meade performed well in this battle, driving the Army of Northern Virginia from Pennsylvania and back into Virginia. Meade remained as the Army of the Potomac's leader for the duration of the war. Ohioan General Ulysses S. Grant, the highest ranking officer in the United States Army for the last two years of the conflict, made his headquarters with Meade's force. Grant directed Meade to continuously attack the South's Army of Northern Virginia, even if the Union force lost more men in a battle or had to withdraw from the battlefield. While the Army of the Potomac lost more men at the Battles of the Wilderness, Spotsylvania Court House, and Cold Harbor in 1864, the North's constant attacks severely weakened the South's ability to wage war, forcing the Army of Northern Virginia to surrender in April 1865. The Army of the Potomac disbanded at the Civil War's conclusion.