Aurora was originally two villages: East Aurora, incorporated in 1845,on the east side of the river, and West Aurora, formally organized on the west side of the river in 1854. In 1857, the two towns joined officially, incorporated as the city of Aurora. As representatives could not agree which side of the river should house the public buildings, most public buildings were built on or around Stolp Island in the middle of the river.
The heavy industries on the East side provided employment for generations of European immigrants, who came from Ireland, Great Britain, Scandinavia, Luxembourg, Germany, France, and Italy. Aurora became the economic center of the Fox Valley region. The combination of these three factors—a highly industrialized town, a sizable river that divided it, and the Burlington railroad's shops—accounted for much of the dynamics of Aurora's political, economic, and social history. The city openly supported abolitionism before the American Civil War. Mexican migrants began arriving after the Mexican Revolution of 1910. Socially, the town was progressive in its attitude toward education, religion, welfare, and women. The first free public school district in Illinois was established in 1851 here and the city established a high school for girls in 1855.
The city developed as a manufacturing powerhouse and continued until the early 1970s, when the railroad shops closed. Soon many other factories and industrial areas relocated or went out of business. By 1980, there were few industrial areas operating in the city, and unemployment soared to 16%. During the late 1970s and early 1980s, development began of the Far East side along the Eola Road and Route 59 areas. While this was financially beneficial to the city, it drew off retail businesses and manufacturing from downtown and the industrial sectors of the near East and West Sides, respectively, weakening them. In the mid-1980s crime rates soared and street gangs started to form.
During this time Aurora became a much more ethnically diverse city. The Latino population began to grow rapidly in the city in the 1980s. In the late 1980s, several business and industrial parks were established on the city's outskirts.
Today, Aurora is an ethnically diverse city and one of only three cities in Illinois that span four counties. Historic areas downtown are being redeveloped, and new developments are being built all over the city.