Horseracing has been around since ancient times. Chariot, and even mounted, horse races, were some of the most popular attractions in some of the first Olympic games in Athens, Greece. In ancient Rome, chariot and mounted horseracing were a near-obsession, although the fall of the Roman Empire in the fifth century A.D. quickly ended the sport's popularity, at least for the time being. Horses soon became necessary for travel and transportation, and were also used for warfare.

This period in history highlights the significance of breeding within the industry. When Arabian horses traveled West with Muslim missionaries who conquered Spain, English knights realized that they could breed slower, weaker English horses with the strong, more agile Arabian horses of the East. As these horses had high levels of endurance and speed, the English began in the twelfth century, to race them on four-mile courses. Saddle racing between two horses quickly became an instant favorite among English royalty, and the crowd placed wagers among themselves that were based heavily upon the King's favorites. Horseracing, therefore, became known as "the sport of king's." Horseracing actually became a professional sport in the early eighteenth century, when tracks appearing throughout England allowed faster horses to compete for increasingly large purses in heats of more than just two horses at a time. Horseracing had emerged as a profitable enterprise for breeders, trainers, jockeys, and finally, betters.

In 1750, the English Jockey Club, which oversees horseracing in the U.K., was formed. It defined racing standards, which led to the creation of certain races that indicate excellence within the industry. Today, English racing is still governed by the same body, which created the five English "classics." These races are the 1,000 Guineas, Epsom Oaks, and the English Triple Crown, which includes the 2,000 Guineas, the Epsom Derby, and the St. Leger Stakes.

European-style horseracing traveled to America via the "New World" settlers from England. The first track was built on Long Island in 1665. Southern colonies could not open tracks until the late seventeenth century, however, when land became over used in the production of tobacco. Southerners were then able to build racetracks on the fallow land. For years after, racing, although not officially an organized sport in the U.S., was characterized by the rivalry between North and South. In the South, Williamsburg, Virginia, became the center of racing, while New York remained the horseracing capital of the North. After the Civil War, racing finally became an organized sport in America, and tracks began to spring up in the West as the East recovered from post-war trauma. Racing quickly became the most popular attraction in America. More than 300 racetracks were in operation by 1890, but corruption was rampant due to a lack of official wagering standards.

In 1894, the American Jockey Club was established in order to bring some legitimacy to horseracing. Corruption, however, remained widespread and intolerable, and many states began to ban horserace wagering. By the early 1900s, the industry was in dire straits. Racing nearly disappeared in the U.S. because the sport did not have the strict set of rules and regulations that govern it today. Loopholes within the industry allowed insiders, who often "rigged" the races, to take advantage of those with less experience and knowledge. As a result, racing now has many officials who monitor the track to ensure that the sport is accurate and fair. The Kentucky Derby was able to initiate a turnaround with the introduction of the pari-mutuel wager in 1908, and as a consequence, states began to reopen their doors to racing. The pari-mutuel wagering pool was initiated by the use of the "toteboard," or "board," which displays race times and results, and provides the odds for each horse based on the mutuel pool of bets. Inventions such as the mechanical starting gate prevented starting-line disagreements, and the photo-finish camera allowed indisputable results. Technological advances in the early part of the twentieth century were important for horseracing because they assured more honesty and therefore encouraged participation.

Since that time, fans loyal to certain horses or certain tracks have created a following within the industry. Today, the most popular races in the U.S. include the Santa Anita Derby, the Jockey Gold Cup, the Travers, the Breeders' Cup, and the Triple Crown, which consists of the Kentucky Derby, Preakness, and Belmont Stakes.