American Civil War: General Ambrose Burnside is relieved of command of the Army of the Potomac after the disastrous Fredericksburg campaign. He is replaced by Joseph Hooker.

Ambrose Everts Burnside was an American army officer and politician who became a senior Union general in the American Civil War and a three-time Governor of Rhode Island, as well as being a successful inventor and industrialist.

The Army of the Potomac was the primary field army of the Union army in the Eastern Theater of the American Civil War. It was created in July 1861 shortly after the First Battle of Bull Run and was disbanded in June 1865 following the surrender of the Confederate Army of Northern Virginia in April.

The Battle of Fredericksburg was fought December 11–15, 1862, in and around Fredericksburg, Virginia, in the Eastern Theater of the American Civil War. The combat between the Union Army of the Potomac commanded by Maj. Gen. Ambrose Burnside and the Confederate Army of Northern Virginia under Gen. Robert E. Lee included futile frontal attacks by the Union army on December 13 against entrenched Confederate against a feature of the battlefield that came to be remembered as the 'sunken wall' on the heights overlooking the city. It is remembered as one of the most one-sided battles of the war, with Union casualties more than twice as heavy as those suffered by the Confederates. A visitor to the battlefield described the battle as a "butchery" to U.S. President Abraham Lincoln.

Joseph Hooker was an American Civil War general for the Union, chiefly remembered for his decisive defeat by Confederate General Robert E. Lee at the Battle of Chancellorsville in 1863.