The first known Europeans to reach Prairie du Chien were French explorers Jacques Marquette and Louis Joliet, who arrived by canoe on June 17, 1673, discovering a route to the Mississippi River. Later travel between Canada and the Mississippi River continued to pass through Prairie du Chien, although routes via the Illinois River were also used. In 1685, the French explorer Nicolas Perrot established a trading post in the area as part of the large and lucrative French fur trade industry. After John Jacob Astor's machinations had closed the entire government fur trade factory systemMueller, Ken S. (2014). Senator Benton and the People. Northern Illinois University Press, pp. 99, 103. and the federal factory established in Prairie du Chien in 1815,Wesley, Edgar Bruce (1935). Guarding the frontier. The University of Minnesota Press, p. 41. the American Fur Company became established in the area and later built the Astor Fur Warehouse, an important building in the regional fur trade, which was centered in Prairie du Chien. Prairie du Chien's significance as a center of the fur trade did not diminish until the mid-19th century, when European demand declined, as did game stock.
