Burnside, Ambrose Everett (1824–1881), a United States army officer. He was born in Liberty, Indiana, and graduated from West Point. In the Civil War he was at Bull Run, South Mountain, and Antietam. In the autumn of 1862 he replaced General George B. McClellan as commander of the Army of the Potomac. In December he was defeated by General Lee and lost 12,600 men in the battle of Fredericksburg. Burnside was relieved of his command shortly afterward, but later received another command and served under Grant. Burnside left the army in 1864.

Ambrose E. BurnsideAmbrose E. Burnside

After the war Burnside was elected governor of Rhode Island and also served that state in the U.S. Senate (1875–81). Burnside popularized muttonchop side whiskers, which became known as burnsides. (The term “sideburns,” referring to shorter side whiskers, also comes from his name.)