The park includes 1,469 acres (5.94 km2) that was once the 19th-century estates of George C. Taylor and J. Neal Plum. Islip's founder, William Nicoll, originally built his estate on this property. The Long Island State Park Commission, led by Robert Moses, expropriated the property in 1924, an action found to be illegal by the state's highest court on the grounds that the law did not permit such expropriation when the Commission did not have the funds to pay for the property; however, in the meantime, the Commission had retained control of the property.[5] Despite opposition from wealthy local residents, the parkland was finally purchased by New York State with the aid of a donation from August Heckscher.