Newburgh is located on the west shore of the Hudson River on the lands of the Waoranek peoples, who were described by the Europeans who first encountered them as a close-knit, loving and peaceable group. The Waoranek were part of the Lenape tribe of the Algonquin nation. Around them in the bay were other related bands also part of the greater Lenape-Algonquin peoples. The Waoranek lived in dome-shaped shelter huts built of bark-covered sapling frames. They grew a few seasonal crops of beans, corn and squash, and they hunted and fished along the streams and the great river. They had no horses and walked everywhere or paddled the river in dugout canoes.
Henry Hudson, an Englishman sailing under contract to the Dutch government, was the first European to explore the river as far north as Newburgh. His ship the Half Moon came up the river in to Newburgh bay in 1609, and his first mate's journal entry for that evening notes this as "a pleasant place to build a town." Hudson sailed away the next morning.
When the first white people came ashore to settle, it was the Waoranek who shared and sustained and taught them about this new world and who gave settlers the very land they lived on — the concept of land ownership being utterly foreign to them. The Waoranek moved on to the west and north as Europeans began to build on and cultivate the acres from the Quassaick Creek to Balmville.
The place name "Quassaick" appears on a map drawn in 1656 by the prominent Dutch settler Adrian Van der Donck.