Windsor, also known as New Windsor, is a village in Rivoli Township, Mercer County, Illinois, United States. The population was 720 at the 2000 census. The official name is the Village of Windsor, but New Windsor is also used by the village such as the New Windsor Fire Department. Windsor apartments for rent comparison page shows most up to date rent information on Windsor apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.