Pierre-Esprit Radisson (1636/1640–1710) was a French coureur des bois and explorer in New France. He is often linked to his brother-in-law Médard des Groseilliers. The decision of Radisson and Groseilliers to enter the English service led to the formation of the Hudson's Bay Company. His career was particularly notable for its repeated transitions between serving Britain and France.

A coureur des bois or coureur de bois were independent entrepreneurial French Canadian traders who travelled in New France and the interior of North America, usually to trade with First Nations peoples by exchanging various European items for furs. Some learned the trades and practices of the indigenous peoples.