Randolph was incorporated as a township by an act of the New Jersey Legislature on January 1, 1806, from portions of Mendham Township. Portions of the township were taken on April 1, 1869, to create Dover Town within the township, which became an independent municipality as of March 5, 1896. Other portions of the township were taken to create Port Oram (June 26, 1895, now Wharton), Mine Hill Township (March 2, 1923) and Victory Gardens (June 20, 1951). The creation of Victory Gardens created a small triangular exclave of the township, surrounded by Victory Gardens to the southeast and Dover to the northwest.