

The latter were part of the Omaha before splitting off into a separate tribe in the mid-18th century. The Omaha speak a Siouan language of the Dhegihan branch, which is very similar to that spoken by the Ponca. The Omaha people migrated to the upper Missouri area and the Plains by the late 17th century from earlier locations in the Ohio River Valley. Its total land area is 307.03 sq mi (795.2 km 2) and the reservation population, including non-Native residents, was 4,526 in the 2020 census. The Omaha Reservation lies primarily in the southern part of Thurston County and northeastern Cuming County, Nebraska, but small parts extend into the northeast corner of Burt County and across the Missouri River into Monona County, Iowa.

There were 5,427 enrolled members as of 2012. The Omaha ( Omaha-Ponca: Umoⁿhoⁿ) are a federally recognized Midwestern Native American tribe who reside on the Omaha Reservation in northeastern Nebraska and western Iowa, United States.
