<P> An unidentified French explorer called this body of water "river des Illinois" after the Illinois Indians who were not, however, usually present in this area . Rather, the earliest known inhabitants were descendants of Caddoans who built the Spiro Mounds at Spiro, Oklahoma . In the 18th century, the Illinois River country was a hunting ground for the Osage Indians . Cherokee began to migrate into the area about 1800 . U.S. Army Major James Wilkinson reported passing the mouth of this river in 1806 . In 1828, the river was designated as a main waterway for the Cherokees </P> <P> The Illinois Confederation included the Peoria, Miami, Wei and Kaskaskia tribes . These tribes shared similar language culture and customs and were all classified as Algonquin . The Miami word Ilaniawaki, meaning "real or original ones," became the French term Illinois . </P> <P> Lake Tenkiller, created by damming the Illinois River beginning in 1947 with completion in 1953, has attracted tourists and fishermen to this once sparsely settled area . Seventy miles of the river between Lake Tenkiller and the Arkansas border, flowing through the Cookson Hills, have been supervised by the Oklahoma Scenic Rivers Commission, currently headed by Ed Fite since 1970 . </P> <P> The spring - fed river rises in the Ozark Mountains in the northwest corner of Arkansas, in Washington County southwest of Fayetteville, near the communities of Hogeye and Onda . The stream flows north parallel to Arkansas Highway 265 then turns northwest passing under U.S. Route 62 northeast of Prairie Grove . It continues north - northwest passing under Arkansas Highway 16 west of Savoy and forming a portion of the east boundary of the Ozark--St. Francis National Forest . The stream flows through a portion of the national forest and enters Benton County . Near Robinson the stream flows under U.S. Route 412 and turns to the west paralleling that route . It passes north of Pedro then under Route 412 again and turns to the southwest . It passes under Arkansas 16 again and Arkansas Highway 59 to the southeast of Siloam Springs . The stream leaves Arkansas at the southwest corner of Benton County and enters Lake Frances in Oklahoma . </P>

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