Father Louis Hennepin, O.F.M. baptized Antoine, (12 May, 1626 – c. 1705) was a Catholic priest and missionary of the Franciscan Recollect order (French: Récollets) and an explorer of the interior of North America.
At the request of Louis XIV the Récollets sent four missionaries to New France in May 1675, including Hennepin, accompanied by René Robert Cavelier, Sieur de la Salle. In 1678 Hennepin was ordered by his provincial superior to accompany La Salle on a voyage to explore the western part of New France. Hennepin was 39 when he sailed in 1679 with La Salle from Canada through the Great Lakes aboard Le Griffon to explore the unknown West. Local historians credit the Franciscan Recollect friar with being the first European to step ashore at the site of present-day Hannibal, Missouri. Two great waterfalls were brought to the world's attention by Louis Hennepin: Niagara Falls, with the most voluminous flow of any in North America, and the Saint Anthony Falls in what is now Minneapolis, the only waterfall on the Mississippi River.
Most placed named after Hennepin are found in the United States:
Hennepin has been denounced by many historians and historical critics as an arrant falsifier. Certain writers have sought to repel this charge by claiming that the erroneous statements are in fact interpolations by other persons. The weight of the evidence is however adverse to such a theory.