Horace is a city in Cass County, North Dakota, United States. As of the 2010 census the population was 2,430. From 2000 to 2010, Horace was the fastest-growing city in North Dakota in terms of percent increase, increasing 165.6% over that decade from a population of 915 in 2000.
The city is a suburb of the Fargo-Moorhead metropolitan area. It is the nineteenth-largest city in North Dakota. Horace was founded in 1882 at a time of widespread European-American settlement in the territory.
A post office has been in operation at Horace since 1875. The city is named after Horace Greeley of Chappaqua, New York, editor of the New York Tribune. Greeley encouraged western settlement with the motto "Go West, young man".
The city is bordered on the west by the Sheyenne River, a tributary of the Red River of the North. To reduce damage from seasonal flooding, which sometimes was very severe, the state and federal government collaborated on the Sheyenne Diversion Project, constructing a canal and associated support in 1990-1992 to move Sheyenne flood waters to the west and south of Horace, and north past the western side of West Fargo.