Louis Joliet (1645-1700), French-Canadian explorer, who led an expedition to explore the upper Mississippi River with Jesuit missionary Jacques Marquette. He was born probably in Beaupré, near the city of Québec, and educated in a Jesuit seminary for the priesthood. He also studied briefly in France, but in 1668, upon his return to New France (France's North American colonial empire), he abandoned the church to become a trader among the indigenous peoples. In 1669 he met Jacques Marquette. In 1672 Joliet, already familiar with the region, was chosen to lead an expedition in search of the upper reaches of the Mississippi River. Father Marquette was named chaplain for the party. The expedition, joined by five woodsmen, left Saint Ignace (now in Michigan) on May 17, 1673. They crossed Lake Michigan, ascended the Fox River, and descended the Wisconsin River. On June 17, 1673, the expedition entered the Mississippi River. The party then followed the Mississippi southward to a point below the mouth of the Arkansas River before turning back. Marquette remained at Lake Michigan while Joliet continued on to Québec, reaching it in 1674. On the return portion of the voyage Joliet lost his records in a canoe accident, but he replaced them from memory. Later Joliet explored in the region of Labrador and Hudson Bay. In 1697 he was appointed royal hydrographer of New France.