During the French and Indian War (the North American theater of the Seven Years' War), British colonial officers suspected that Acadians were aligned with France, after finding some Acadians fighting alongside French troops at Fort Beauséjour. Though most Acadians remained neutral during the war, the British, together with New England legislators and militia, carried out the Great Expulsion (Le Grand Dérangement) of the Acadians between 1755 and 1764. They forcefully deported approximately 11,500 Acadians from the maritime region. Approximately one-third perished from disease and drowning. The result was described as an ethnic cleansing of the Acadians from Maritime Canada.