Wyndmere is a city in Richland County, North Dakota, United States. The population was 454 at the 2020 census. Wyndmere was founded in 1…Wyndmere is a city in Richland County, North Dakota, United States. The population was 454 at the 2020 census. Wyndmere was founded in 1883 and named after Windermere in England. It is part of the Wahpeton, ND–MN Micropolitan Statistical Area.