Minto is a city in Walsh County, North Dakota, United States. The population was 616 at the 2020 census. Minto was founded in 1881. …Minto is a city in Walsh County, North Dakota, United States. The population was 616 at the 2020 census. Minto was founded in 1881. A post office has been in operation at Minto since 1880. Minto was incorporated in 1883. The city was named after Minto, Ontario, the native home of a large share of the early settlers. The St. Joseph's Chapel was built by Polish immigrants in 1907.