 The population increased by 3,454 (+67.9%) from the 5,090 counted in the 2000 Census, which had in turn increased by 1,216 (+31.4%) from the 3,874 counted in the 1990 Census.Mansfield was first formed on November 6, 1688, and reformed by Royal charter on May 9, 1770.Mansfield was incorporated by an act of the New Jersey Legislature on February 21, 1798, as one of New Jersey's initial group of 104 townships.