Breese is a city in Clinton County, Illinois, United States. Breese is the most populous city completely within Clinton County. As of the 2020 census, the population was 4,641, the majority of whom are of German ancestry. Breese is part of the Metro-East region of the Greater St. Louis metropolitan area.

Clinton County is located in the U.S. state of Illinois. At the 2020 census, the population was 36,899. Its county seat is Carlyle.