Macomb County is a county on the eastern shore of the U.S. state of Michigan. It is part of the Detroit metropolitan area, bordering Detroit to the north and containing many of its northern suburbs. Its seat of government is Mt. Clemens, and its largest community is Warren. As of the 2020 census, the county had a population of 881,217, making it the third-m…Macomb County is a county on the eastern shore of the U.S. state of Michigan. It is part of the Detroit metropolitan area, bordering Detroit to the north and containing many of its northern suburbs. Its seat of government is Mt. Clemens, and its largest community is Warren. As of the 2020 census, the county had a population of 881,217, making it the third-most populous county in the state, behind neighboring Wayne and Oakland. Macomb County contains 27 cities, townships and villages, including three of the ten most-populous municipalities in Michigan. Most of this population is concentrated south of Hall Road, one of the county's main thoroughfares.