Ramsey County, Minnesota (Wikipedia) Ramsey County is a county located in the U.S. state of Minnesota. As of the 2020 census, the population was 552,352, making it the second-most populous county in Minnesota. Its county seat and largest city is Saint Paul, the state capital and the twin city of Minneapolis. The county was founded in 1849 and is named for Alexander Ramsey, the first governor of the Minnesota Territory.