12th Pennsylvania Infantry Regiment

April 22, 1861

Organized at Pittsburg under Colonel David Campbell, Lieutenant Colonel Norton McGiffin and Major Alexander Hays

April 24

Moved to Harrisburg, Pa.

April 25

Reviewed by Governor Curtin and mustered into U.S. service, then immediately moved to York, Pa. by rail as part of Patterson's Deparment of Pennsylvania

May 25

Guard duty on Northern Central Railroad from State line to Baltimore Md. Headquarters at Cockeysville, Md., relieving the 1st Pennsylvania Infantry. Headquarters was at Cockeysville with Companies I and K, the other companies widely scattered until end of enlistment.

August 5, 1861

Mustered out