Fort Menagoueche (French: Fort Menagouèche) 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. Due to the succession of strategic French and British forts at this location, the site was designated a National Historic Site of Canada in 1923.