The Omaha are a federally recognized Native American tribe which lives on the Omaha Reservation in northeastern Nebraska and western Iowa, United States. The Omaha Indian 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. Its total land area is 796.355 km2 (307.474 sq mi) and a population of 5,194 was recorded in the 2000 census. Its largest community is Macy.
They migrated to the upper Missouri area and the Plains by the late 17th century from earlier locations in the Ohio River Valley. The Omaha speak a Siouan language of the Dhegihan branch that is very similar to that spoken by the Ponca. The latter were part of the Omaha before splitting off into a separate tribe in the mid-18th century. They were also related to the Siouan-speaking Osage, Quapaw, and Kansa peoples, who also migrated west under pressure from the Iroquois in the Ohio Valley.
About 1770, the Omaha became the first tribe on the Northern Plains to adopt equestrian culture. Developing “The Big Village” (Ton-wa-tonga) about 1775 in current-day Dakota County in northeast Nebraska, the Omaha developed an extensive trading network with early European explorers and voyageurs. They controlled the fur trade and access to other tribes on the Upper Missouri River.
Omaha, Nebraska, the largest city in Nebraska, is named after them. Never known to take up arms against the U.S., members of the tribe assisted the U.S. during the American Civil War.