The district was created following the 1830 U.S. Census and came into existence in 1833, five months before Chicago was organized as a town; the state was previously represented in the U.S. House of Representatives with representative elected on an at-large basis. The district included Southwestern Illinois until 1853. It included the state's northern edge until 1863. Since that time, the district has included all or part of Cook County; since 1883 the population of the district has been primarily residing on Chicago's South Side. Historical populations reflected waves of immigration into the area: previous majority populations were ethnic Irish, German, and east European. Beginning in the mid-19th century, the Irish were the first to establish their physical and political control of the area within the city's South Side.