It is hard to know exactly who farmed and hunted the rich grasslands and wooded valleys of Illinois in the two centuries or so between the fall of Cahokia and the arrival of the first French explorers and missionaries (and, thus, the beginning of the first written accounts) in the mid- to late 1600s. Some, perhaps most, of these natives would have identified themselves as "Illinik," a word that the French transformed into "Illinois." But even that name described a loose confederation of a number of smaller bands or tribes, including Kaskaskias, Peorias, Tamaroas, Metchigameas, and others. Others, particularly in northeastern Illinois, would have called themselves "Miami."
Even before the first Europeans reached the area, Europe's impact began to be felt in Illinois. The native peoples of Illinois would have noticed first an influx of new people who had been driven from their own villages, fields, and hunting grounds by warfare in the east. Most of them spoke Algonquin languages, like most of the peoples of Illinois, but that did not always insure that they could communicate with each other. These immigrants were refugees from the intense, if intermittent, warfare known as the Iroquois Wars (or Beaver Wars) that lasted from 1640 to 1701. By the early 1640s, the Five Nations of the Iroquois had largely exhausted the beaver population of the Hudson River valley in their trade with the Dutch at Fort Orange (now Albany, N.Y.). The powerful and well-armed Iroquois began to press hard against their neighbors to the north and west, trying to gain control of new hunting grounds and to intercept the furs that the Hurons and other Great Lakes Indians traded to the French at Montreal and Quebec. The force of the Iroquois' onslaught drove many of their smaller, weaker neighbors west, first to the upper Ohio River valley, then to the western Great Lakes region, including Illinois. By the mid-1650s, the impact of this warfare became more direct, as the first Iroquois war parties reached Illinois itself.