Sugar houses in New York City were used as prisons by occupying British forces during the American Revolutionary War. Out of 2,600 prisoners of war captured during the Battle of Fort Washington in November 1776, 1,900 would die in the following months at makeshift prisons throughout the city. At least 17,500 are estimated to have perished under substandard conditions of such sugar houses and British prison ships over the course of the war, more than double that of casualties from battle.