Macro-Siouan languages
In the 19th century, Robert Latham suggested that the Siouan languages are related to the Caddoan and Iroquoian languages. In 1931, Louis Allen presented the first list of systematic correspondences between a set of 25 lexical items in Siouan and Iroquoian. In the 1960s and 1970s, Wallace Chafe further explored the link between Siouan and Caddoan languages. In the 1990s, Marianne Mithun compared the morphology and syntax of all the three families. At present, the Macro-Siouan hypothesis based on relations among Siouan, Caddoan, and Iroquoian is not universally accepted as proven.
Sioux City, Iowa
Iowa is in the tallgrass prairie of the North American Great Plains, historically inhabited by speakers of Siouan languages.
The area of Sioux City was inhabited by Yankton Sioux when it was first reached by Spanish and French furtrappers in the 18th century. The first documented US citizens to record their travels through this area were Meriwether Lewis and William Clark during the summer of 1804. Sergeant Charles Floyd, a member of the Lewis and Clark Expedition, died here on August 20, 1804, the only death during the two and a half-year expedition.