91st Pennsylvania Infantry

91st Pennsylvania Infantry
Pennsylvania flag
Active	December 4, 1861 to July 10, 1865
Country	United States
Allegiance	Union
Branch	Infantry
Engagements	Battle of Fredericksburg Battle of Chancellorsville Battle of Gettysburg Overland Campaign Battle of Five Forks

The 91st Pennsylvania Volunteer Infantry Regiment was a Union infantry regiment that fought in the American Civil War. They wore an americanized zouave uniform that consisted of a dark blue zouave jacket with yellow trimming, dark blue zouave vest with yellow trimming, sky blue sash, sky blue pantaloons, and a red fez with a blue tazzle.

The regiment was raised near Philadelphia during the fall of 1861 and mustered into Federal service on December 4 of that year. Edgar I. Gregory was elected colonel of the regiment, Edward E. Wallace lieutenant colonel,Dr. Isaac D. Knight surgeon major and George W. Todd major. It was ordered to Washington, D.C., the following month and served in garrison duties in the city until August, when it was sent to the Army of the Potomac.