The 157th Pennsylvania Volunteer Infantry was a Union infantry regiment which fought in multiple key engagements during the final years of the American Civil War, including the Battle of Cold Harbor, Siege of Petersburg, and Appomattox Campaign. One of two military units raised at roughly the same time in the Philadelphia area during the fall of 1862, the 157th Pennsylvania was stationed initially at Fort Delaware, beginning in December 1862, and remained there on garrison duty until it was reassigned to the defense of Washington, D.C. during the early winter of 1863. It was then assigned to the Army of the Potomac during the spring of 1864, and sent to the front lines of the war's Eastern Theater, where it remained for the duration of the war. During a reorganization of Union Army units i