Siouan 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.
Sion District
Sion has a population () of . Most of the population () speaks French (31,488 or 85.1%) as their first language, German is the second most common (1,878 or 5.1%) and Portuguese is the third (1,029 or 2.8%). There are 915 people who speak Italian and 20 people who speak Romansh.