Liberty is a town in Sullivan County, New York, United States. The population was 10,159 at the 2020 census. The village is bisected by New York State Route 52 and NY 55, and is crossed by NY 17. The town of Liberty area is credited with providing 303 men who fought in the Revolution. Liberty was carved originally from the then large townshi…Liberty is a town in Sullivan County, New York, United States. The population was 10,159 at the 2020 census. The village is bisected by New York State Route 52 and NY 55, and is crossed by NY 17. The town of Liberty area is credited with providing 303 men who fought in the Revolution. Liberty was carved originally from the then large township of Lumberland and was itself at this time so large that it included the present Towns of Callicoon and Fremont. The Town today covers 85 square miles.