He fought in the Mexican–American War and received the brevet rank of first lieutenant for his services in the battles of Contreras and Churubusco.

[2] During the Civil War, Pitcher led a provisional battalion in the defense of Harpers Ferry in June 1862, where he and his men were among the thousands of Union soldiers who surrendered to Stonewall Jackson.

After being released and exchanged, he served in the Virginia campaign until the battle of Cedar Mountain (August 9, 1862), where he was severely wounded.

He was then brevetted major in the regular army, and three months later was commissioned brigadier general of United States Volunteers.

[1] He died of tuberculosis, on October 21, 1895 in the Fort Bayard Historic District in New Mexico, and was interred in Arlington National Cemetery,[3] along with his sons, Lt. Col. John Pitcher, also a West Point graduate, class of 1876, and Col. William L.