Roscoe is a village in Winnebago County, Illinois, along the Rock River. It is in a suburban area of the Rockford, Illinois Metropolitan Statistical Area. As of the 2010 census, the village population was 10,785, up from 6,244 at the 2000 census. The area has been undergoing a period of rapid growth. There have been numerous border disputes with its neighbor to the west, Rockton, Illinois, and development and annexations continue by both villages. Recent growth has included the Promontory Ridge and Hidden Creek custom home subdivisions east of the Illinois Tollway, I-39/I-90.

Winnebago County is a county located in the U.S. state of Illinois. According to the 2020 census, it had a population of 285,350 making it the seventh most populous county in Illinois behind Cook County and its five surrounding collar counties. Its county seat is Rockford. Winnebago County is the central county of the Rockford metropolitan area.