|Heintzelman, Samuel Peter|
|September 30, 1805
|May 1, 1880
When the Civil War began, Heintzelman was commissioned Colonel in command of the new 17th US Infantry. Three days later, he was promoted to Brigadier General. Heintzelman led troops as they captured Alexandria, and fought at the 1st Bull Run, in which he was wounded while trying to rally his broken 3rd Division in the Union rout. On March 13, he assumed command of the III Corps Army of the Potomac and was promoted to major general in May.
Heintzelman took part in Major Gen. George B. McClellan's Peninsula Campaign. He commanded the III Corps, Army of the Potopmac. Despite the courage he displayed in previous engagements, his performance in the campaign showed him to be an overly cautious field commander. He fought at Yorktown, Williamsburg , Seven Pines, Savage's Station, Glendale, and Malvern Hill. He also served in the Seven Days' Campaign, but was not effective at the 2nd Bull Run, and Chantilly. This would be his last campaign as a corps commander.
In October of 1862, Heintzelman was relieved of corps command and assigned to the Military District of Washington. He remained there for 2 years and was then placed in command of the Northern Department, headquartered in Columbus, Ohio. In the last months of the war, he served on court-martial duty, and retired in 1869. He then became a businessman.