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.
Today’s Frankfort is just a small portion of the original town, which contained the present-day towns of Frankfort, Winterport, Stockton Springs, and Prospect. Ft. Pownall was thus in Frankfort, and the town’s major village was what is now Winterport. Frankfort was a logical place for settlement not only because Verona Island commanded the approach up the river, but because the river above the town froze during the winter, making this the last ice-free port as one ascended — hence the name “Winterport”.
One of the first settlers was Lt. Joshua Treat (1729-1802), the armorer at Ft. Pownall, whose brother became one of the first settlers of Bangor.