1st Regiment, Massachusetts Infantry

Organized at Boston and mustered in Companies "A," "B," "G" and "H" May 23; Companies "D," "F," "K" and "I" May 24 Company "E" May 25, and Company "C" May 27, 1861. Left State for Washington, D. C., June 15, arriving June 17. Attached to Richardson's Brigade, Tyler's Division, McDowell's Army of Northeast Virginia, to August, 1861. Hooker's Brigade, Division of the Potomac, to October, 1861. 1st Brigade, Hooker's Division, Army of the Potomac, to March, 1862. 1st Brigade, 2nd Division, 3rd Army Corps, Army of the Potomac, to March, 1864. 1st Brigade, 4th Division, 2nd Army Corps, to May, 1864. Mustered out May 25, 1864. Expiration of term.