[1] This regiment was organized at Philadelphia and mustered into federal service on May 1, 1861.

[2] In May the regiment was ordered to Baltimore and encamped at Locust Point.

Later, it moved to Patterson's park and at Mount Clare.

It performed guard and police duty in Baltimore.

[3][2] Attached to the defenses of Baltimore in the Department of Annapolis[4] commanded by Brigadier General Benjamin F. Butler[note 1] (until May 15) and then Major General George Cadwalader.