The Peoria Tribe of Indians of Oklahoma is a confederation of Kaskaskia, Peoria, Piankeshaw and Wea Indians united into a single tribe in 1854. The tribes that constitute the Confederated Peorias, as they then were called, originated in the lands bordering the Great Lakes and drained by the mighty Mississippi. They are Illinois or Illini Indians, descendants of those who created the great mound civilizations in the central United States 2,000 to 3,000 years ago.

Forced from their ancestral lands in Illinois, Michigan, Ohio and Missouri, the Peorias were relocated first in Missouri, then to Kansas, and finally to Indian Territory. While in Kansas, increasing encroachment from Euro-Americans in the 1840s and 1850s brought about cooperation among the Peoria, Kaskaskia, Piankeshaw and Wea Tribes to protect their holdings. With the Treaty of May 30, 1854, the United States recognized their cooperation and consented to their formal union as the Confederated Peoria. In addition to this recognition, the treaty also provided for the disposition of constituent tribal lands set aside by the treaties of the 1830s. Ten sections were to be held in common by the new Confederation with each tribal member to receive an allotment of 160 acres and the remaining or "surplus" land to be sold to settlers with proceeds to be used by the tribes.

The Civil War caused considerable turmoil among all the people of Kansas, especially the Indians. After the war, most members of the Confederation agreed to move to Indian Territory under the provisions of the so-called Omnibus Treaty of February 23, 1867. Some tribal members elected at this time to remain in Kansas, separate from the Confederated Tribes, and become U.S. citizens. The lands of the Confederation members in Indian Territory were subject to the provisions of the General Allotment act of 1887. The allotment of all the tribal land was made by 1893 and by 1915, the tribe had no tribal lands or any lands in restricted status. Although the U.S. government's "Termination Policy" terminated supervision of the Peoria Tribe and its property in 1956, federal recognition was restored to the Peoria Tribe in 1978.

Peorias today are maintaining old traditions within a modern context, participating in powwows with neighboring tribes, hosting stomp dances, and holding their own powwow celebrations each June.