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. A settlement subsequently sprang up under its protection, and was named in honor of General John Winslow, of Marshfield, Massachusetts, who had overseen the fort's construction. General Winslow was a descendant of Edward Winslow, a Pilgrim governor of Plymouth Colony who arrived on the Mayflower and founded the town of Marshfield. General Winslow lived in the mansion built in 1699 by his father, Isaac Winslow. The historic Winslow House still stands today in Marshfield and is on the National Register of Historic Places.