Saint Joseph, colloquially known as Saint Joe, is a city in and the county seat of Berrien County, Michigan. It was incorporated as a village in 1834 and as a city in 1891. As of the 2020 census, the city population was 7,856. It lies on the shore of Lake Michigan, at the mouth of the St. Joseph River, about 90 miles (140 km) east-northeast of Chicago. The city and adjacent Benton Harbor are known as the "Twin Cities".