The capital of Illinois is Springfield in the central part of the state. Although today the state's largest population center is in and around Chicago in the northeastern part of the state, the state's European population grew first in the west, with French who settled along the Mississippi River and gave the area the name Illinois Country. After the American Revolutionary War established the United States, American settlers began arriving from Kentucky in the 1780s via the Ohio River, and the population grew from south to north. In 1818, Illinois achieved statehood. After construction of the Erie Canal increased traffic and trade through the Great Lakes, Chicago was founded in the 1830s on the banks of the Chicago River, at one of the few natural harbors on southern Lake Michigan.John Deere's invention of the self-scouring steel plow turned Illinois's rich prairie into some of the world's most productive and valuable farmland, attracting immigrant farmers from Germany and Sweden. The Illinois and Michigan Canal (1848) made transportation between the Great Lakes and the Mississippi River valley faster and cheaper. New railroads carried immigrants to new homes, as well as being used to ship commodity crops to Eastern markets. The state became a transportation hub for the nation.
American scholars previously thought the name "Illinois" meant "man" or "men" in the Miami-Illinois language, with the original iliniwek transformed via French into Illinois. This etymology is not supported by the Illinois language, as the word for "man" is ireniwa, and plural of "man" is ireniwaki. The name Illiniwek has also been said to mean "tribe of superior men", which is a false etymology. The name "Illinois" derives from the Miami-Illinois verb irenwe·wa - "he speaks the regular way". This was taken into the Ojibwe language, perhaps in the Ottawa dialect, and modified into ilinwe· (pluralized as ilinwe·k). The French borrowed these forms, changing the /we/ ending to spell it as -ois, a transliteration for its pronunciation in French of that time. The current spelling form, Illinois, began to appear in the early 1670s, when French colonists had settled in the western area. The Illinois's name for themselves, as attested in all three of the French missionary-period dictionaries of Illinois, was Inoka, of unknown meaning and unrelated to the other terms.