city, seat (1778) of Westchester county, New York, U.S. It lies along the Bronx and Hutchinson rivers. Known to the Wappinger Indians as Quarropas (“White Marshes”), probably for the area's heavy fogs, the site was sold twice (in 1660 and in 1683) by them to different groups, causing long litigation over the title and delays in the settlement of the area. An established community by 1735 within the town (township) of Rye, White Plains became the centre of iron-mining activity in Westchester and also served as a crossroads for several transportation lines. The New York Provincial Congress met there on July 9, 1776, approved the Declaration of Independence, and proclaimed the creation of the state of New York. On October 28, 1776, at the battle on Chatterton Hill (commemorated as White Plains National Battlefield Site), George Washington (Washington, George) outmaneuvered the British general Lord Howe (Howe, William Howe, 5th Viscount) and was able to slip his troops away to fortified lines farther north. The Elijah Miller House (1738), which served as Washington's headquarters, has been restored.

Connected by rail to New York City (21 miles 【34 km】 southwest) in 1844, White Plains grew as an urban core and a residential and retail-trade centre. A range of light manufactured goods are now produced, and there are corporate offices and headquarters for many firms. The city's educational institutions include the New York School for the Deaf (1817) and Pace University at White Plains (1975). The State University of New York (New York, State University of (SUNY)) College at Purchase (1969) is nearby. Inc. village, 1866; city, 1916. Pop. (1990) 48,718; (2000) 53,077.