Major General Joseph
Mansfield
Army of the Potomac, XII Corps Commander
Union Army
Nearly all of Joseph Mansfield's life was spent in the U.S. Army. He entered the United States Military Academy at the age of thirteen, and he died in the Battle of Antietam at the age of fifty eight. Joseph King Fenno Mansfield was born on December 22, 1803 in New Haven, Connecticut. He graduated from West Point in 1822, and he became an engineer officer. During the Mexican War, Major Mansfield served as General Zachary Taylor's chief engineer. He quickly earned promotions to colonel.
The missions of Brigadier General Mansfield's commands during the Civil War were to defend Washington, D. C. As Confederate General Robert E. Lee moved to encircle Washington, D. C., General George McClellan's Army of the Potomac intercepted them, and the Battle of Antietam occurred on September 17, 1862. General Mansfield had been in command of XII Corps of the Army of the Potomac for only five days when the battle occurred. He was wounded in the stomach as he led his troops across a corn field toward the East Wood, and he died the next day. He was among the 23,110 casualties of the bloodiest single day in American military history. Joseph Mansfield was promoted posthumously to major general.