Independence Township was originally created on November 11, 1782, from Hardwick Township, while the area was still part of Sussex County, and was incorporated as one of the state's initial group of 104 townships by an act of the New Jersey Legislature on February 21, 1798. Most of Independence Township became part of the newly created Warren County on November 20, 1824, with the remainder becoming part of Green Township in Sussex County. Portions of the township were taken to form Hackettstown (March 9, 1853) and Allamuchy Township (April 4, 1873). The township was named for American independence.