1864
September 15 Organized as the 212th Volunteers at Pittsburg, Pennsylvania under Colonel Charles Barnes, Lt. Colonel Joseph B. Copeland, and Majors Robert Long, Joseph Kemp and Frank White
September 17 Moved to Washington, D.C. Armed as infantry and attached to 2nd Brigade, DeRussy’s Division, 22nd Corps
September 29-November 17 Guard Orange & Alexandria Railroad between Alexandria and Manassas, Va., wth headquarters at Fairfax Court House
December Garrison Forts Marcy, Ward, Craig, Aeno, Albany and Lyon, Defenses of Washington, south of the Potomac assigned to 1st Brigade, DeRussy’s Division, 22nd Corps. The regiment was drilled as artillery under the instruction of Captain Gustavus Braun of Battery B, who had served in the 2nd Pennsylvania Artillery.
1865
June 13 Mustered out at Fort Ethan Allen