Radisson, Pierre Esprit (1636–1710), a French fur trader and explorer of North America. He came to Canada in 1651. Soon after, he was captured by the Iroquois and adopted by them. He remained with them for a few years, and then, as a fur trader, traveled the West with his brother-in-law Médard Chouart, Sieur des Groseilliers. Unwilling to share profits with the French governor of Canada, in 1664 they entered English service. Six years later he and Groseilliers helped set up the Hudson's Bay Company. Radisson later returned to France and served in the French navy. His vivid account of early travels in North America was published in 1885 as Voyages of Peter Esprit Radisson.