Cadillac is a city in and county seat of Wexford County in the U.S. state of Michigan. The population was 10,371 at the 2020 census, making it t…Cadillac is a city in and county seat of Wexford County in the U.S. state of Michigan. The population was 10,371 at the 2020 census, making it the second most-populated city in the Northern Michigan region, after Traverse City.