Brunswick is a town in Rensselaer County, New York, United States that was originally settled in the early 18th century. During its history, it had been part of Albany County, Rensselaerswyck, and Troy, before its incorporation in 1807. It is bordered on the west by the city of Troy; on the north by Schaghticoke and Pittstown; on the east by Grafton; and on the south by Poestenkill and North Greenbush. The population was 11,941 at the 2010 census.