Samuel Peter Heintzelman
Samuel P. Heintzelman
Place of burial	Forest Lawn Cemetery, Buffalo, New York
Allegiance	United States of America Union
Service/branch	Union Army
Years of service	1826 - 1869
Rank	Major General
Battles/wars	Seminole War Mexican-American War Cortina Troubles American Civil War

Samuel Peter Heintzelman (September 30, 1805 – May 1, 1880) was a United States Army General. He served in the Seminole War, the Mexican-American War, the Cortina Troubles, and the American Civil War, rising to the command of a corps.

Heintzelman was born in Manheim, Pennsylvania, to Peter and Ann Elizabeth Grubb Heintzelman. He graduated from the United States Military Academy in 1826 and was commissioned a brevet second lieutenant in the 3rd U.S. Infantry, July 1, 1826, then in the 2nd U.S. Infantry in the and served on the Northern frontier at Fort Gratiot, Fort Mackinac and Fort Brady. On March 4, 1833, he was promoted to First Lieutenant, and served on quarter-master's duty in Florida during the Second Seminole War. July 7, 1838, he was appointed Captain in the Quartermaster's Department, remaining in Florida until the close of the war in 1842. In 1847, during the Mexican American War he joined General Winfield Scott's Army in Mexico, taking part in several engagements, for which he was brevetted Major, October 9, 1847. In 1848-49 he accompanied his regiment around Cape Horn to California, and for several years served in California the Arizona Territory.

In December, 1851, Major Heintzelman led the Yuma Expedition from the post of San Diego to put down the Yuma uprising, called the Yuma War. His expedition established Fort Yuma and peace was made in October, 1852. He received the brevet of Lieutenant-Colonel for his conduct in the campaign against the Yuma Indians and in March 3, 1855, he was promoted to Major of the 1st U.S. Infantry and served with that regiment on the Texas frontier. In 1859, during the First Cortina War in Texas, he was largely responsible for the defeat of Juan Cortina's forces.^[1]

Heintzelman was the first president of the Sonora Exploring and Mining Company which established the Cerro Colorado, Arizona mining town in southern Arizona. The town became famous during the American Civil War for the massacre of mine employees by Mexican outlaws and buried treasure.

At the outbreak of the Civil War, Heintzelman became the colonel of the 17th Pennsylvania Infantry, and was soon promoted to command of a division in the Army of Northeastern Virginia. He was wounded at the July 1861 First Battle of Bull Run, but soon recovered and resumed his duties.

Heintzelman was in overall command of the 2nd Michigan Infantry regiment that was responsible for the raid, ransacking, and devastation of the Pohick Church in Lorton, Virginia, on November 12, 1861. The historic church was built in 1769 by George Washington, George Mason, and George William Fairfax, among others, and restored after the War of 1812 by President Martin Van Buren, John Quincy Adams, and Francis Scott Key, among others. This ransacking caused the loss of a myriad of irreplaceable artifacts.

He commanded the III Corps of the Army of the Potomac in the Peninsula Campaign and at Second Bull Run. He was commissioned as a brevet brigadier general in the regular army and a major general in the volunteers. Relieved of his command in late 1862, he later commanded XXII Corps, assigned to the defense of Washington, D.C., where he remained for the rest of the war, commanding the Northern Department.

Heintzelman retired in 1869 as a major general in the regulars. He died in Washington, D.C., and is buried in Forest Lawn Cemetery, Buffalo, New York.

• List of American Civil War generals

• Eicher, John H., and Eicher, David J., Civil War High Commands, Stanford University Press, 2001, ISBN 0-8047-3641-3.
• Pohick Church history

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