A horse race is a competition of speed and stamina between horses, typically on a flat course. While the sport has developed from a primitive contest of chariot and mounted (bareback) races to today’s spectacle with its enormous fields of runners, sophisticated electronic monitoring equipment, and immense sums of money bet by millions of people, the essential concept remains the same: the horse that crosses the finish line first is the winner. While some argue that the practice is inhumane or corrupted by doping and overbreeding, others consider it an exciting and rewarding form of entertainment and a pinnacle of achievement for the horses that compete in the sport.

The earliest horse races were match races between two or at most three horses, with the owner providing the purse; betting was a simple wager. When an owner withdrew, he would forfeit half or, later, the entire purse. Such agreements were recorded by disinterested third parties who came to be known as keepers of the match book. One such keeper at Newmarket in England published An Historical List of All Match Races Run (1729).

Horse racing has been around for thousands of years, with organized horse races occurring throughout the world. It was a popular pastime in ancient Greece, where both four-hitch chariot and mounted races were held at the Olympic Games over the period 700-40 bce. The Romans also held horse races. Organized horse racing was introduced to America by Samuel Ogle, who is credited with introducing the sport to Maryland in 1745. Ogle’s horse Tryal beat the American horse Selima in a match race that was later deemed “the most important event of its kind in Colonial America.”

In order to make the sport as fair as possible, a system of handicapping was established. In a handicapped race, the racing secretary assigns weight allowances designed to equalize the chances of winning for the entrants, taking into consideration their previous record and types of victories. This system of handicapping is widely used in horse racing throughout the world.

Many horse races have been marred by controversy over doping, animal cruelty, and the general corruption of the sport. In the early part of the 20th century, horse racing was plagued by an unprecedented series of fatal accidents involving racehorses in which riders fell off and were killed. The resulting outrage caused the sport to undergo major reforms, including the introduction of the National Thoroughbred Racing Association in 2021.

In addition to stricter drug control regulations, the NTRA has instituted uniform standards for post-race testing and in-competition inspections. These standards are intended to give the sport the appearance of a level playing field that is consistent and predictable across the 38 states with active thoroughbred racing. In addition, the NTRA has adopted rules in 2021 that are meant to decrease the risk of catastrophic injuries such as fractures and concussions. By requiring that injured racehorses be subjected to blood tests after the race, the NTRA hopes to identify changes in messenger RNA that could indicate an injury.