Waukegan is a city in Lake County, Illinois, United States, and its county seat. Located 36 miles north of Chicago, Waukegan is a satellite city …Waukegan is a city in Lake County, Illinois, United States, and its county seat. Located 36 miles north of Chicago, Waukegan is a satellite city within the greater Chicago metropolitan area. As of the 2020 census, its population was 89,321, making it the most populous city in Lake County, the seventh-most populous city within the Chicago metropolitan area and the 10th-most populous city in Illinois. However, unlike nearby wealthy North Shore suburbs, Waukegan has long been classified by the Illinois state government as overall "socioeconomically distressed" despite having some middle class inhabitants.