Hastings is a city mostly in Dakota County, Minnesota, of which it is the county seat, with a portion in Washington County, Minnesota, United …Hastings is a city mostly in Dakota County, Minnesota, of which it is the county seat, with a portion in Washington County, Minnesota, United States. It is near the confluence of the Mississippi, Vermillion, and St. Croix Rivers. The population was 22,154 at the 2020 census. It is named for the first elected governor of Minnesota, Henry Hastings Sibley.