Illinois is from a French rendering of ilinwe (pl. iliniwek). Ilinwe is in turn an Odawa language rendering of irenweewa. (The Ottawa were a neighboring tribe, whom the French met first.) Irenweewa means he-who-speaks-the-common-way in the Illinois Confederation language but the confederation word for themselves was inoca (inoka). Unlike the plural form iliniwek, the term illini does not appear to have an historic linguistic connection.
When French explorers first journeyed to the region from Canada in the 17th century, they found the area inhabited by a vigorous, populous Algonquian-speaking nation. What we know today about the Illinois is based on the historical account Jesuit Relations, written by French Jesuits. The missionaries who lived among the various native nations wrote the Relations and sent the reports back to their superiors in France. One name for an Illinois Confederation tribe, the Cahokia, was used as a name for a French settlement, now Cahokia, Illinois, near what are now called the Cahokia Mounds, the remains of a large pre-Columbian city. However, it is currently unknown whether the Illinois Confederation peoples, including the Cahokia, have any relationship to the earlier native builders of the mounds civilization.
The Illinois spoke various dialects of the Miami-Illinois language, one of the Algonquian language family. Among the earliest renditions of the modernized, Anglicized term "Illiniwek" were Liniouek (1656), "Aliniouek" (1658), "Alimiwec" (1660), "iriniȣak" (1662; the old French symbol ȣ, often printed as the numeral '8' which it resembles, represents the vowel /o/ in Illinois), and "Ilinioüek" (1667). In 1210 Father Claude Allouez, S.J. referred to a band of natives as "IlimoucK" (the editor added an alternative spelling "Iliniouek") in one sentence and "Ilinioüetz" in the next. The English translation changed the latter spelling to "Iliniouetz." In the variable spelling of the times, the name of Allouez was also spelled "Alloues," "Alloez," Aloes," "Aloez," "Aloues," and "Daloes" in these early records.
Illinois was not the tribes' name for themselves, or autonym. Rather, Illinois is a French transliteration of an Old Ottawa term for them, or exonym: /ilinwe/ 'he speaks the ordinary way'. This in turn was presumably borrowed from the Illinois or Old Miami verb /irenweewa/, which has the same meaning as the Ottawa form. The Illinois' autonym was Inoka (sometimes spelled Inoca), as it appears in all three Illinois dictionaries from the late 17th/early 18th century. For example, in the Illinois-French dictionary from the early 18th century often attributed to Gravier, the word 'Inȣca' is translated as Illinois peuple. Or, in the 1725 LeBoullenger French-Illinois dictionary, the same word is spelled inoca, and translated Illinois.
In the 17th century, the Illinois suffered from a combination of exposure to Eurasianinfectious diseases, to which they had no natural immunity, and warfare by the expansion of the Iroquois into the eastern Great Lakes region. The Iroquois had hunted out their traditional lands and sought more productive hunting and trapping areas. They sought furs to purchase European goods in the fur trade. Many of the Illinois migrated to present-day eastern Kansas to escape the pressure from other tribes and encroaching European settlers.
The Illinois lived in a seasonal cycle related to cultivation of domestic plants and hunting, with movement from semi-permanent villages to hunting camps. They planted crops of maize (corn), beans, and squash, known as the "Three Sisters". They prepared dishes such as sagamite. They also gathered wild foods such as nuts, fruit, roots and tubers. In the hunting season, the men hunted bison, deer, elk, bear, cougar, lynx, turkey, geese and duck. Women prepared the meat for preservation and the hides for equipment and clothing. They tapped maple trees and made the sap into a drink or boiled it for syrup and sugar.
Thwaites, R.G. (1899) The Jesuit relations and allied documents travels and explorations of the Jesuit missionaries in New France, 1610-1791, 236. The English translation is on the next page.
Costa, David J. 2008. "On the Origins of the Name “Illinois”", Le Journal 24/4: 6-10.
"The Illiniwek", The Lewis and Clark Journey of Discovery, National Park Service, accessed 29 Sep 2009
Costa, David J. 2000. "Miami-Illinois Tribe Names". In John Nichols, ed., Papers of the Thirty-first Algonquian Conference 30-53. Winnipeg: University of Manitoba.
Costa, David J. 2008. "On the Origins of the Name “Illinois”." Le Journal 24/4: 6-10.
Costa, David J.; Wolfart, H.C., ed. (2005). "The St. Jérôme Dictionary of Miami-Illiniois" (PDF). Papers of the 36th Algonquian Conference. Winnipeg: University of Manitoba. pp. 107–133. Retrieved March 7, 2012.
Masthay, Carl, editor. Kaskasia Illinois-to-French Dictionary. St. Louis, Missouri: Carl Masthay. p. 757. ISBN 0-9719113-04.