Île aux Noix Île aux Noix is an island on the Richelieu River in Quebec , close to Lake Champlain . The island is the site of Fort Lennox National Historic Site of Canada . Politically , it is part of Saint - Paul - de - l ' Île - aux - Noix . Background . Île aux Noix is a island in the Richelieu River . The French and Indian War caused the French to build a fort in 1759 , named " fort de l ' Isle aux Noix " , to slow the British advance on Montreal , but were forced to surrender it in 1760 . In 1775 , the island was taken by American forces , and used as a base by the American generals Philip Schuyler and Richard Montgomery for attacks on Montreal and Quebec . The Americans used the island again in 1776 during their retreat from Canada . Their army spent 10 days on the island : more than 900 American soldiers died and were buried in two mass graves on Isle aux Noix . The British then built a new fort in 1778 and named it the " fort of Isle aux Noix " . During the War of 1812 , the British used the island to supply their operations against the American fleet on Lake Champlain . The present Fort Lennox was built from 1819 to 1829 , when the old fortifications were completely demolished . It remained a military post until 1870 and is now a popular tourist location . The Île aux Noix Naval Shipyard was a Royal Navy yard from 1812 to 1834 in Quebec and served the RN ' s Lake Champlain fleet during the War of 1812 . HMS " Confiance " was one of several warships built here . French fortifications . The population of New France during the last years of the Seven Years ' War lived through difficult times . It faced an appreciable reduction in support from the home country , at a time when France ' s resources were being stripped by the situation on the European continent . In the colony from year to year , civilians and soldiers saw their hopes crushed as they worked out strategies , which were constantly deprived of the necessary royal support . The campaigns of 1759 and 1760 provide strong evidence of this situation and it is in this context that the strategists decided to build a fort on Île aux Noix . From August 16 to 28 , 1753 , French soldiers commanded by Colonel Bougainville , withstood a siege led by Amherst . Bougainville realised that the fort of Île aux Noix could not resist a longer siege . On August 27 , Bougainville had his troops silently leave the island in the middle of the night and headed to Montreal where he hoped his soldiers could help . The siege of Isle aux Noix ended on August 28 , when a group of about 40 French soldiers surrendered to the British forces . The last French governor - general of New France , Pierre François de Rigaud , Marquis de Vaudreuil - Cavagnal , surrendered to British Major General Jeffrey Amherst on September 8 , 1760 . France finally ceded Canada to the British in the Treaty of Paris , signed on February 10 , 1763 . The strategic importance of Île aux Noix decreased as soon as the conquest of Canada was complete in 1760 . Amherst had not thought it wise to preserve the French fortifications on Île aux Noix and therefore he ordered the razing of the entrenchments to salvage the construction materials , which might be reused at Crown Point . First British fortifications . After New France became a British colony , there was not much use for Île aux Noix as a military post . The French fort was destroyed . Yet after the American invasion of the province of Quebec in 1775 - 1776 by means of the Richelieu River , the British authorities decided to build a new fort on the island in 1778 . It was used during the War of 1812 . That fort was demolished to make place for fort Lennox . American occupation . In 1775 , the island was taken by American forces and used as a base by the American generals Philip Schuyler and Richard Montgomery for attacks on Montreal and Quebec . After being defeated at Quebec and abandoning Montreal , the Continental Army regrouped at the island in 1776 in its retreat from the province of Quebec . The site returned to British hands as an important frontier fort , now its southernmost on the Richelieu . Blockhouses were constructed in 1779 to resist further attack . A much more impressive fortification was built from 1779 to 1782 . Second British fortifications . During the War of 1812 , the race for naval superiority in the area re - established the military importance of the island , which became the main support point for the British navy on this border . The flagship of the British squadron on Lake Champlain , , a 36 gun 5th rate frigate , became the largest vessel ever constructed at Île aux Noix . Postwar . The postwar period provided another opportunity to rethink the defensive system on the Upper Richelieu in the light of the experience acquired in the War of 1812 . This time the endless debate between Saint - Jean - sur - Richelieu , Quebec and Île aux Noix brought the engineer officers into direct opposition to the naval officers . The engineers favoured Saint - Jean because of the many possibilities of bypassing Île aux Noix , while the naval officers , convinced by the experiences of the recent war , preferred Île aux Noix because of its advantages against an operation over water . The latter were further favoured by the activities of the Americans a short distance from the border , since the construction of Fort Montgomery provided the competent British authorities with an argument for supporting Île aux Noix . Internment camp . From 1940 the island was the home of an internment camp which held European Jewish refugees who had been forcibly removed from Britain . The camp was initially called Camp I , later Camp No . 41 . Internees were treated as enemy aliens , and only after a year did the Canadian authorities begin to treat them as refugees . They were still not free to leave the camp , however , in some cases until 1944 .