Twelve U.S. states have designated a horse breed as the official state horse. The first state horse was designated in Vermont in 1961. The most recent state designations occurred in 2010, when North Carolina and South Carolina both declared state breeds. There have been proposals to designate a state horse in Oregon as well as in Arizona (where an ongoing campaign sought to designate the Colonial Spanish Horse as the state horse prior to the state centennial in 2012), but neither proposal is yet successful.  In one state, North Dakota, the state horse is officially designated the "honorary state equine."  Two additional states have not designated a specific state horse, but have designed a horse or horse breed as its official state animals: the horse in New Jersey and the Morgan horse breed in Vermont.
Some breeds, such as the American Quarter Horse in Texas and the Morgan horse in Vermont and Massachusetts, were named as the state horse because of the close connection between the history of the breed and the state. Others, including the Tennessee Walking Horse and the Missouri Fox Trotter, include the state in the official breed name. School children have been persuasive lobbyists for the cause of some state horses, such as the Colonial Spanish Horse being named the state horse of North Carolina due to the presence of the Spanish-descended Banker horses in the Outer Banks,  while others have been brought to official status through the lobbying efforts of their breed registries.
Official state horses are one of many state symbols officially designated by states. Each state has its own flag and state seal, and many states also designate other symbols, including animals, plants, and foods. Such items usually are designated because of their ties to the culture or history of that particular state. In addition to being state symbols in their own right, horses have also appeared in state symbols; for example, a horse's head appears on the Seal of New Jersey.
|Alabama||Racking Horse||The Racking Horse is a breed of horse known for its ambling gait. The breed association is headquartered in Decatur, Alabama.||
|Florida||Florida Cracker Horse||The Florida Cracker Horse was first brought to what is now Florida in the 1500s by Spanish explorers, and it played a large part in the development of the state's cattle and general agriculture industries.||2008||
|Idaho||Appaloosa||The Appaloosa has made a substantial contribution to Idaho history, mainly through its association with the Nez Perce Indian tribe.||1975|||
|Kentucky||Thoroughbred||The Thoroughbred is the center of a multi-billion dollar breeding and racing industry in Kentucky.||1996||
|Maryland||Thoroughbred||Maryland has a long history of breeding and racing Thoroughbreds, and today maintains an extensive network of breeding farms, training centers and racecourses.||2003||
|Massachusetts||Morgan||The foundation sire of the Morgan breed, named Figure, was born in West Springfield, Massachusetts in 1789.||1970|||
|Missouri||Missouri Fox Trotter||The Fox Trotter is a gaited breed developed in the Missouri Ozarks.||2002|||
|New Jersey||Horse (state animal)||As of the designation of the horse as the state animal, New Jersey contained over 4,500 horse farms housing almost 40,000 horses and played host to a horse industry that extensively contributed to the preservation of natural lands in the state.||1977|||
|North Carolina||Colonial Spanish Mustang||This state breed references the Banker horse of the Outer Banks, descended from Spanish stock.||2010|||
|North Dakota||Nokota (honorary equine)||The Nokota developed in the badlands of southwestern North Dakota, and are named after the Nakota Indian tribe that inhabited the area.||1993|||
|South Carolina||Carolina Marsh Tacky||The Marsh Tacky was developed in the swampy Low Country region of South Carolina, and has played an integral part in the state's history.||2010||
|Tennessee||Tennessee Walking Horse||The Tennessee Walker is a gaited breed initially developed in middle Tennessee.||2000||
|Texas||American Quarter Horse||The history of the Quarter Horse is closely intertwined with that of Texas, where the breed was used for ranching and racing. The American Quarter Horse Association is headquartered in Amarillo, Texas.||2009|||
|Vermont||Morgan (state animal)||The Morgan breed was developed mainly in Vermont, where the founding stallion, Figure, lived most of his life and died in 1821.||1961||
|Arizona||Colonial Spanish Horse||The Colonial Spanish Horse has a long history in Arizona, mainly through the Wilbur-Cruce strain originally bred near Arivaca.||2010 (re-proposed in 2011)||
|Oregon||Kiger Mustang||The Kiger Mustang is a strain of Mustang found in a feral state only in southeastern Oregon.||2001|||
Horses, both official state horses and not, are present in the emblems of several states.
|Delaware||State quarter – Caesar Rodney on horseback||1999|||
|Idaho||License plate – Appaloosa||
|Kentucky||State quarter – Thoroughbred||2001|||
|Maryland||State Seal – Knight on horseback||1969|||
|Nevada||State quarter – Mustang||2006|||
|New Jersey||State seal and coat of arms – Horse||1928||
|Pennsylvania||Coat of arms and flag – Horses||Coat of arms: 1875
- "About Us". Arizona Colonial Spanish Horse Project. Archived from the original on July 7, 2011. Retrieved February 10, 2011.
- " North Dakota State Equine," State of North Dakota.
- "NC okays Outer Banks mustangs as state horse". WVEC Television, Inc. June 2, 2010. Archived from the original on June 5, 2010. Retrieved March 19, 2011.
- "History". Racking Horse Breeders' Association of America. Archived from the original on November 28, 2010. Retrieved February 5, 2011.
- "CS/CS/HB 131 – State Symbols". Florida House of Representatives. Retrieved October 5, 2010.
- "History of the Cracker Horse". Florida Cracker Horse Association. Archived from the original on March 24, 2011. Retrieved March 19, 2011.
- "Appaloosa History". Appaloosa Horse Club. Retrieved February 5, 2011.
- "State Symbols". Kentucky Legislative Research Commission. Retrieved February 5, 2011.
- "State Horse". Commonwealth of Kentucky. Archived from the original on June 7, 2013. Retrieved April 12, 2014.
- "Maryland State Horse – Thoroughbred Horse". State Symbols. State of Maryland. Retrieved February 5, 2011.
- "Breeders Association". Maryland Horse Breeders Association. Archived from the original on April 20, 2011. Retrieved March 19, 2011.
- "Part One: Concise Facts". Secretary of the Commonwealth of Massachusetts. Retrieved February 5, 2011.
- "About the Missouri Fox Trotter Horse Breed". Missouri Fox Trotting Horse Breed Association. Retrieved February 5, 2011.
- "Chapter 173, Laws of 1977". State of New Jersey. Archived from the original on October 1, 2011. Retrieved March 19, 2011.
- Dutson, Judith (2005). Storey's Illustrated Guide to 96 Horse Breeds of North America. Storey Publishing. pp. 192–195. ISBN 1-58017-613-5.
- "State Heritage Horse". Carolina Marsh Tacky Association. Retrieved February 4, 2011.
- "The Marsh Tacky Horse – Yesterday and Today". Carolina Marsh Tacky Association. Retrieved March 17, 2011.
- "Tennessee Symbols and Honors" (PDF). Tennessee Blue Book. State of Tennessee. Retrieved February 5, 2011.
- "History and Description". Tennessee Walking Horse Breeders' and Exhibitors' Association. Archived from the original on July 17, 2011. Retrieved March 19, 2011.
- "Quarter Horse Named Official State Horse of Texas". The Horse. August 19, 2009. Retrieved February 5, 2011. (Registration required (help)).
- "State Animal: Morgan Horse". State of Vermont. Archived from the original on November 10, 2010. Retrieved February 5, 2011.
- "History". American Morgan Horse Association. Archived from the original on February 25, 2011. Retrieved March 19, 2011.
- "History of the Horses". Arizona's Colonial Spanish Horse Project. Archived from the original on July 7, 2011. Retrieved March 17, 2011.
- Steves, David (January 23, 2001). "Senator trots out horse nominee". The Register-Guard. Eugene, Oregon. Retrieved November 1, 2009.
- "Delaware State Quarter – 1999". United States Mint. Retrieved March 16, 2011.
- "Title 49: Motor Vehicles, Chapter 4: Motor Vehicle Registration, 49-420D: Appaloosa License Plates". Idaho Legislature. Retrieved March 19, 2011.
- "State Seal". State of Maryland. Retrieved April 12, 2014.
- Aldrich, Sean (February 2006). "Wild at Heart: Mustangs outran other candidates for the Nevada quarter". Numismatist: 40. Archived from the original on December 25, 2010. Retrieved February 10, 2011.
- Zatz, Arline (2004). Horsing Around in New Jersey: The Horse Lover's Guide to Everything Equine. Rutgers University Press. p. 1. ISBN 0-8135-3334-1.
- "The Great Seal of the State of New Jersey". State of New Jersey. Archived from the original on May 3, 2011. Retrieved March 19, 2011.
- "Pennsylvania: Past and Present – Symbols". Pennsylvania Historical and Museum Commission. Archived from the original on October 14, 2007. Retrieved March 16, 2011.
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