Fort Beauséjour () (later known as Fort Cumberland) was built by the French during Father Le Loutre's War from 1751–1755; it is located at the Isthmus of Chignecto in present-day Aulac, New Brunswick, Canada. The property is now a National Historic Site of Canada officially known as Fort Beauséjour – Fort Cumberland National Historic Site. To maintain the land route between Louisbourg and Quebec, the French built this fort and two satellite installations: one at present-day Port Elgin, New Brunswick (Fort Gaspareaux) and the other at present-day Saint John, New Brunswick (Fort Menagoueche).