Six years after coming to New York in 1692, 31 year-old Caleb Heathcote (pronounced "Hethcut") devised a plan to create a manor under royal patent. Heathcote bought a large section of Richbell's land, then acquired a western piece called "Fox Meadows" from the Siwanoy. The manor ultimately encompassed over 6,000 acres and stretched from Long Island Sound to the Bronx River, from White Plains to New Rochelle and what is now Mt. Vernon (then only a small village called East Chester). Heathcote named it "Scarsdale" after his home in Derbyshire, England. In 1701, the year the Crown granted his patent, Scarsdale Manor's total population was twelve souls.
The town saw fighting during the American Revolution when the Continental and British armies clashed briefly at what is now the junction of Garden Road and Mamaroneck Road. The British commander, Sir William Howe, lodged at a farmhouse on Garden Road that remains standing. Scarsdale's wartime history formed the basis for James Fenimore Cooper's novel, The Spy, written while the author lived at the Angevine Farm in the present-day Heathcote section of town.