Nassau County, New York: History
The area now designated as Nassau County originally constituted the eastern 70% of Queens County, one of the original twelve counties of New York State formed in 1683, and was then contained within two towns: Hempstead, and Oyster Bay. In 1784, the Town of North Hempstead was formed through secession by the northern portions of the Town of Hempstead. Nassau County was formed in 1899 by the division of Queens County, after the western portion of Queens had become a borough of New York City in 1898, as the three easternmost towns seceded from the county.
When the first European settlers arrived, among the Native Americans to occupy the present area of Nassau County were the Marsapeque, Matinecoc, and Sacatogue. Dutch settlers in New Netherland predominated in the western portion of Long Island, while English settlers from Connecticut occupied the eastern portion. Until 1664, Long Island was split, roughly at the present border of Nassau and Suffolk counties, with the Dutch establishing ownership of what would become Nassau County, and Connecticut claiming the fiture Sussex County territory. The Dutch did grant an English settlement in Hempstead (now in western Nassau), but drove settlers from the present-day eastern Nassau hamlet of Oyster Bay as part of a boundary dispute. In 1664, all of Long Island became part of the English Province of New York within the Shire of York. Present-day Queens and Nassau were then just part of a larger North Riding. In 1683, the colonial territory of Yorkshire was dissolved, Suffolk County and Queens County were established, and the local seat of government was moved west from Hempstead to Jamaica (now in New York City).
By 1700, virtually none of Long Island's area remained unpurchased from the Native Americans by the English colonists, and townships controlled whatever land had not already been distributed. The courthouse in Jamaica was torn down by the British during the American Revolution to use the materials to build barracks.
In 1784, following the American Revolutionary War, the Town of Hempstead was split in two, when Patriots in the northern part formed the new Town of North Hempstead, leaving Loyalist majorities in the Town of Hempstead. Around 1787, a new Queens County Courthouse was erected (and later completed) in the new Town of North Hempstead, near present-day Mineola (now in Nassau County), known then as Clowesville. …