Ossining is a town in Westchester County, New York, United States. The population was 37,674 at the 2010 census. It contains two villages, the Village of Ossining and part of Briarcliff Manor, the rest of which is located in the Town of Mount Pleasant. It is the location of Sing Sing maximum-security prison.
Frederick Philipse bought the area which presently constitutes the Town of Ossining from the Sint Sinck Indians in 1685. The Sint Sinck are members of the Matinecock (Algonquin) tribe, who originally resided in the area of Cow Neck Peninsula on Long Island, New York. His Manor extended from Spuyten Duyvil Creek on the border between present day Manhattan and the Bronx to the Croton River. The last Lord of the Manor, Frederick Philipse III, was a Loyalist in the American Revolutionary War who fled to England, so the State of New York confiscated the manor in 1779.
In 1813, the village of Sing Sing was incorporated, and in 1845, the New York State Legislature created a new town out of the northern part of what had been the Town of Mount Pleasant. A local Indian authority suggested the town be named Ossinsing, a different form of the name Sing Sing. One year later the last "s" was removed for ease in pronunciation. In 1881, the town considered changing its name to "Garfield Plains" to honor the recently assassinated President of the United States, James Garfield, but dropped the idea after the much larger city of White Plains in southern Westchester County objected. In 1901, to prevent confusion of goods made in the village with Sing Sing prison-made items, local officials had the village name changed to Ossining as well.
In 1902 an area east of the village of Ossining, then known as Whitson's Crossing, was incorporated as the village of Briarcliff Manor.