Frankfort is the oldest town on the Penobscot River, first settled in the 1760s by Massachusetts soldiers from nearby Fort Pownall. With the end of the French and Indian War, the Penobscot Valley became part of New England, and more specifically Massachusetts, leading to the first cautious encroachments by English-speaking settlers on the lands of the Penobscot Indians. This process, which would begin in Frankfort, would end with the founding of Bangor, Brewer, Orono, Old Town and other inland settlements, and the eventual restriction of the Penobscot people to their major village at "Indian Old Town", or the present Penobscot Indian Reservation.