Fort Frederick was a British fort at what is now Saint John, New Brunswick, Canada. It was built during the St. John River Campaign of the French and Indian War. It was one of three significant forts which the British built on the major rivers in the Northeast to cut off the natives' water way to the ocean to prevent attacks on the British settlers.

Fort Menagoueche was a French fort at the mouth of the St. John River, New Brunswick, Canada. French Officer Charles Deschamps de Boishébert et de Raffetot and Ignace-Philippe Aubert de Gaspé built the fort during Father Le Loutre's War and eventually burned it themselves as the French retreated after losing the Battle of Beausejour. It was reconstructed as Fort Frederick by the British.