Cahokia Indians. A tribe of the Illinois confederacy, usually noted as associated with the kindred Tamaroa. Like all the confederate Illinois tribes they were of roving habit until they and the Tamaroa were gathered into a mission settlement about the year 1698 by the Jesuit Pinet. This mission, first known as Tamaroa, but later as Cahokia, was about the site of the present Cahokia, Illinois, on the east bank of the Mississippi, nearly opposite the present St Louis. In 1721 it was the second town among the Illinois in importance. On the withdrawal of the Jesuits the tribe declined rapidly, chiefly from the demoralizing influence of the neighboring French garrison, and was nearly extinct by 1800. With the other remnant tribes of the confederacy they removed, about 1820, to the west, where the name was kept up until very recently, but the whole body is now officially consolidated under the name Peoria.