Illinois Illinois State Government Illinois has a silent “s” at the end, because it’s of French origin. “Illinois” means “Land of Illini,” giving a nod to the Native American population. “Illini” is the Algonquin word for “man” or “warrior.” Capital: Springfield Largest Cities: Aurora, Carbondale, Charleston, Chicago, Cicero, Decatur, East St. Louis, Elgin, Joliet, Naperville, Peoria, Quincy, Rock Island, Rockford, Village of Arlington Heights, Waukegan Present Constitution Drafted: 1970 Entered Union: December 3, 1818 (21) Motto: “State Sovereignity, National Union” State Flower: Violet State Tree: White Oak State Bird: Cardinal State Dog: Not Specified State Insect: Monarch Butterfly State Song: “Illinois” Nickname: Prairie State, The Land of Lincoln