Siouan languages
Siouan or Siouan–Catawban is a language family of North America that is located primarily in the Great Plains, Ohio and Mississippi valleys and southeastern North America with a few other languages in the east.
Lumbee
After repeated rejections under the Croatan, Cherokee and Cheraw labels, the proto Lumbee petitioned the United States Bureau of Indian Affairs in 1924 for recognition as "Siouan" Indians. This petition was rejected largely on the grounds that Siouan was a language, not a tribe. Moreover, there was no record of the Lumbee or their ancestors having ever spoken the Siouan or any other Indian language.