Cook County

Cook County was incorporated in 1831 and named for Daniel Pope Cook, an early Illinois statesman. It achieved its present boundaries in 1839. Within a century, the county recorded explosive population growth, going from a trading post village with a little over six hundred residents to four million, rivaling Paris by the Great Depression. During the first half of the 20th century it had the absolute majority of Illinois’s population.   Today’s population of Chicago is comparable to the 1920’s.

(source: Wikipedia)