New Rockford is a city in Eddy County, North Dakota, United States. It is the county seat of Eddy County. The population was 1,361 at the 202…New Rockford is a city in Eddy County, North Dakota, United States. It is the county seat of Eddy County. The population was 1,361 at the 2020 census. New Rockford was founded in 1883. New Rockford was founded in 1883, when the Great Northern Railway arrived in the area.