Hallock is a city in and the county seat of Kittson County, Minnesota, United States. The population was 906 at the 2020 census. Hallock …Hallock is a city in and the county seat of Kittson County, Minnesota, United States. The population was 906 at the 2020 census. Hallock was platted in 1879. The city was named for Charles Hallock, an American writer. Hallock was incorporated as a city in 1887. A post office has been in operation at Hallock since 1879.