|central North America|
|Linguistic classification:||One of the world's primary language families|
|ISO 639-2 / 5:||sio|
Pre-contact distribution of the Siouan–Catawban languages
Authors who call the entire family Siouan distinguish the two branches as Western Siouan and Eastern Siouan or as Siouan-proper and Catawban. Others restrict the name "Siouan" to the western branch and use the name Siouan–Catawban for the entire family. Generally, however, the name "Siouan" is used without distinction.
Siouan languages can be grouped into the Western Siouan languages and Catawban languages. The Western Siouan languages can be divided into Missouri River languages (such as Crow and Hidatsa), Mandan, Mississippi River languages (such as Dakotan, Chiwere-Winnebago, and Dhegihan languages), and Ohio Valley Siouan branches. The Catawban languages consist only of Catawban and Woccon.
There is certain amount of comparative work in Siouan–Catawban languages. Wolff (1950–51) is among the first and more complete works on the subject. Wolff reconstructed the system of proto-Siouan, and this was modified by Matthews (1958); the system generally accepted is:
With respect to vowels, five oral vowels are being reconstructed /*i, *e, *a, *o, *u/ and three nasal vowels /*ĩ, *ã, *ũ/. Wolff also reconstructed some consonantal clusters /*tk, *kʃ, *ʃk, *sp/.
The Yuchi isolate may be the closest relative of Sioux–Catawban.
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, this Macro-Siouan hypothesis is not considered proved, and the similarities between the three families may instead be due to their protolanguages having been part of a sprachbund.
- Parks, Douglas R.; & Rankin, Robert L. (2001). "The Siouan languages." In R. J. DeMallie (Ed.), Handbook of North American Indians: Plains (Vol. 13, Part 1, pp. 94–114). W. C. Sturtevant (Gen. Ed.). Washington, D.C.: Smithsonian Institution. ISBN 0-16-050400-7.
- Voegelin, C.F. (1941). "Internal Relationships of Siouan Languages". American Anthropologist 42: 246–249.