(born before Sept. 21, 1645, probably Beaupré, near Quebec—died after May 1700, Quebec province) French Canadian explorer and cartographer. He led an expedition in the Great Lakes region in 1669. In 1672 he was commissioned by the governor of New France to explore the Mississippi in the company of Jacques Marquette and five others. In 1673 the party set out in birchbark canoes across Lake Michigan, following the Fox and Wisconsin rivers to the Mississippi, then down the Mississippi to its confluence with the Arkansas. They concluded that the river flowed south to the Gulf of Mexico and not, as hoped, into the Pacific Ocean. After their return, Jolliet explored areas of Hudson Bay and the Labrador coast.
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