sentences:  Another colony, more populous than that of Raleigh, was developed at the island during the American Civil War.After Union forces took over the island in 1862, slaves migrated there for relative freedom, as they were considered contraband by the military, who would not return them to the Confederates.The Army established the Roanoke Island Freedmen's Colony in 1863, an important social experiment as part of the US government's developing policies related to the future of the slaves in freedom.