Calvin is a city in Cavalier County, North Dakota, United States. The population was 15 at the 2020 census. Calvin was founded in 1905. …Calvin is a city in Cavalier County, North Dakota, United States. The population was 15 at the 2020 census. Calvin was founded in 1905. Likely the most historic structure left in town, the Calvin AF & AM Corinthian Masonic Lodge Number 78, was burned and razed in May 2014, after the upper floor had collapsed sometime between 2010 and 2012.