Hawthorne is a borough in Passaic County, New Jersey, United States. As of the 2010 United States Census, the borough's population was 18,791 reflecting an increase of 573 from the 18,218 counted in the 2000 Census, which had in turn increased by 1,134 from the 17,084 counted in the 1990 Census.Hawthorne was originally part of the now-defunct Manchester Township, which was later subdivided to create Hawthorne, Haledon, North Haledon, Prospect Park, Totowa, The Heights/Columbia Heights District of Fairlawn and most of the First Ward of Paterson. The Borough of Hawthorne was incorporated from portions of Manchester Township by an act of the New Jersey Legislature on March 24, 1898. The borough was named for novelist Nathaniel Hawthorne.