 As a result of the Continental Army’s reorganization of January 1, 1776, Fairfield was assigned to Col. John Greaton’s 24th Continental Regiment with the rank of lieutenant, and served with this regiment throughout 1776 fighting at the Battle of Trois-Rivières, Quebec (June 8) and the Battle of Valcour Island, Lake Champlain (October 11).The 24th Continental rejoined Gen. Washington’s main army in November 1776 in Morristown, New Jersey, in anticipation of the year-end expiration of many of its troops’ enlistments, and in anticipation of winter quartering.Matthew re-enlisted and was promoted to captain on January 1, 1777, as part of the reorganization of the 13th Massachusetts Regiment (Col. Edward Wigglesworth commanding).