Illinois Confederation

The Illinois Confederation, also referred to as the Illiniwek or Illini, were a loosely organized group of 12 or 13 tribes who lived in the Mississippi River Valley. Eventually, member tribes occupied an area reaching from Lake Michigan to Iowa, Illinois, Missouri, and Arkansas. The five main tribes were the Cahokia, Kaskaskia, Mitchigamea, Peoria, and Tamaroa. Other related tribes included the Maroa (which may have been the same as the Tamaroa), Tapourao, Coiracoentanon, Espeminka, Moingwena, Chinkoa, and Chepoussa. By 1700, only the Cahokia, Kaskaskia, Michigamea, Peoria, and Tamaroa remained.

The spelling "Illinois" was derived from the transliteration by French explorers of iliniwe into the orthography of their own language. The Illinois are estimated to have numbered approximately 10,500 individuals at the time of intensive European contact in the late seventeenth century—a figure that would decline, within a century, to fewer than 500, largely consequent war and disease brought about by the arrival of French colonists and the westward pressure of the Iroquois Confederacy. In 1832, the last of the Illinois homelands were ceded, and survivors were removed to Kansas. An 1854 treaty acknowledged the practical merger of surviving groups and classified them as the Confederated Peoria. The remnants of these tribal groups are now known as the federally recognized Peoria Tribe of Indians and reside in present-day Oklahoma.