Poggatacut also known as Youghco or Poggatticut, was sachem of the Manhasset Indian people of Shelter Island, New York and elder brother to Montaukett Sachem Wyandanch. Sachem Poggatacut and his wife Aswaw granted possession to Lion Gardiner for Gardiners Island in 1639. It was conveyed when they deeded Manchonat, an Island between the north and south fork in exchange for goods and alliance. By 1644 he had united the Corchaug, Shinnecock, Manhassets and Montaukett before retreating as Grand Sachem to his redoubt on Shelter Island, relinquishing control over the tribes to his younger brother, sachem Wyandanch. As “Sachem of Paumanacke", as Long Island was called, he was empowered to make treaties for the Montauketts.

Shelter Island is an island town in Suffolk County, New York, United States, near the eastern end of Long Island. The population was 3,253 at the 2020 United States census.