He served in the provincial militia during Queen Anne's War. In 1710 he commanded a militia regiment that saw action at the capture of Port Royal, Acadia. Following the victory he went London with Francis Nicholson, the expedition's leader, where he was "bigg with expectation" of advancement. His expectations were rewarded with a commission as lieutenant governor of the Province of Massachusetts Bay, serving under Governor Joseph Dudley. He then returned to Massachusetts, where he was again active in the defense of the colonies, serving at Fort William and Mary in New Hampshire, and reporting on the frontier defenses in what is now southern Maine (but was then part of Massachusetts).