Because there had been little direct action at Boston after the Battle of Bunker Hill in June, many units stationed in the American camps besieging the town were bored with garrison life and eager for action. Arnold selected a force of 750 men from the large number who expressed interest in the proposed expedition. Most of these were divided into two battalions: one commanded by Lieutenant Colonel Roger Enos and the other by Lieutenant Colonel Christopher Greene. The rest were placed in a third battalion under Daniel Morgan that included three companies—250 men—of Continental riflemen from Virginia and the Pennsylvania Rifle Regiment. These frontiersmen, from the Virginia and Pennsylvania wilderness, were better suited to wilderness combat than to a siege, and had been causing trouble since arriving outside Boston. The entire force numbered about 1,100. Among the volunteers were other men who rose to later prominence during and after the war, including Aaron Burr, Return J. Meigs, Henry Dearborn, and John Joseph Henry.