Jacksonville is an unincorporated community located within four municipalities originally in Pequannock Township, in Morris County, in the U.S. state of New Jersey. Located in the area of Jacksonville Road (County Route 504) and Sunset Road, the area consists of residential houses and a church. In the 19th century, the area known as Jacksonville was wholly located within Pequannock Township. A school existed a few hundred feet south of the Church. Upon the creation of the township of Montville in 1867, Jacksonville was split between these two municipalities.
In 1922, the borough of Kinnelon and the borough of Lincoln Park were created out of a portion of Pequannock Township, further splitting Jacksonville into a portion of four municipalities.