Rawdon was sent to Philadelphia with dispatches and returned to New York for the winter, where he raised a regiment, called the Volunteers of Ireland, recruited from deserters and Irish Loyalists. Promoted colonel in command of this regiment, Rawdon went with Clinton to Philadelphia. starting out on 18 June 1778, he went with Clinton during the withdrawal from Philadelphia to New York, and saw action at the Battle of Monmouth. He was appointed adjutant general. Rawdon was sent to learn news of the Battle of Rhode Island.