sentences:  After suffering dramatic population decreases by the early 17th century due to infectious diseases from Europe, which they had no immunity to, most of the survivors were pushed out by encroaching Tuscarora, an Iroquoian-speaking tribe.In 1585, the Ralph Lane Colony explored the Chowan River at least as far up as present-day Winton.In 1622, the John Pory Colony led an expedition from Virginia to the Chowan River.