The Regiment was authorized on April 23, 1775 in the Massachusetts State Troops as Thomas’ Regiment. Organized in spring 1775 at Roxbury to consist of 10 companies from northern Plymouth County. Adopted on June 14, 1775 into the Continental Army and assigned to the Main Continental Army. Redesignated on July 1, 1775 as Bailey’s Regiment. It was assigned on July 22, 1775 to Thomas’ Brigade, an element of the Main Continental Army. Consolidated on January 1, 1776 with Cotton’s Regiment, and consolidated unit redesignated as the 23d Continental Regiment, an element of Thomas’ Brigade, to consist of 8 companies. Reassigned on February 9, 1777 from Clinton’s Brigade and assigned to the Northern Department. It was assigned on August 13, 1777 to the 4th Massachusetts Brigade, an element of the Northern Department. Re-designated on August 1, 1779 as the 2nd Massachusetts Regiment. Reassigned on January 1, 1781 from the 4th Massachusetts Brigade and assigned to the 2d Massachusetts Brigade, an element of the Highland’s Department. Disbanded on November 3, 1783 at West Point, New York.