The Indian history of the area centers about three distinct tribes of the region, the Newichawannocks on the banks of the Piscataqua, the Sokokis, or the Saco tribe living in the vicinity of the Saco River, and the Abenaki tribes from Canada. The Newichawannocks, also called the Piscataquas, were based nearer to the people of Berwick. The first attack at Berwick was upon the dwelling house of Richard Tozier, situated near the present South Berwick line. There were more attacks from both sides and it makes no sense now to try and decide who was to blame. One thing is certain. All sides endured many hardships during the early years as Berwick was struggling to become a community.

By 1647 the settlements at Kittery had become incorporated as the first town in Maine. Old Kittery included what is now Eliot, South Berwick, North Berwick and Berwick. The community of Newichawannok (Old Berwick) had become the parish of Unity. This parish of Unity was sometimes designated as Kittery Commons, and Kittery, North Parish. Eventually the inhabitants of this area ceased using the name Unity and their records referred to this area as Barwick.