[1] Originally built as a wooden palisaded fort in 1754, during the French and Indian War, only a single blockhouse survives.

[2] The fort guarded Wabanaki canoe routes that reached to the St. Lawrence and Penobscot Valleys via the Chaudière-Kennebec and Sebasticook-Souadabscook rivers.

[7]) The palisaded defense was intended to prevent Canadiens and their Native American allies from using the Kennebec River valley as a route to attack English settlements.

In 1754, Fort Halifax was built by order of the Massachusetts General Court on the peninsula at the confluence of the Sebasticook and Kennebec rivers.

[5] A settlement subsequently sprang up under its protection, and was named in honor of Major-General John Winslow, of Marshfield, Massachusetts who had overseen the fort's construction.

[8][9] In 1755, the commanding officer, Captain William Lithgow, discontinued Major-General Winslow's original plan for the fort, citing limited manpower and expense.

[5] In September 1775, Fort Halifax hosted troops under Colonel Benedict Arnold on their expedition to Quebec City.

[13] In the nineteenth and twentieth centuries, ownership of Fort Halifax blockhouse changed hands numerous times.

[10][16] The Town of Winslow in 2011 drafted plans to rebuild some of the fort and to expand and improve interpretive displays, trails, and recreational opportunities at the site.