Chariot racing (Greek: ἁρματοδρομία harmatodromia, Latin: ludi circenses) was one of the most popular ancient Greek, Roman, and Byzantine sports. Chariot racing was dangerous to both drivers and horses as they often suffered serious injury and even death, but these dangers added to the excitement and interest for spectators. Chariot races could be watched by women, who were barred from watching many other sports. In the Roman form of chariot racing, teams represented different groups of financial backers and sometimes competed for the services of particularly skilled drivers. As in modern sports like soccer, spectators generally chose to support a single team, identifying themselves strongly with its fortunes, and violence sometimes broke out between rival factions. The rivalries were sometimes politicized, when teams became associated with competing social or religious ideas. This helps explain why Roman and later Byzantine emperors took control of the teams and appointed many officials to oversee them.
The sport faded in importance in the West after the fall of Rome. It survived for a time in the Byzantine Empire, where the traditional Roman factions continued to play a prominent role for several centuries, gaining influence in political matters. Their rivalry culminated in the Nika riots, which marked the gradual decline of the sport.
It is unknown exactly when chariot racing began, but it may have been as old as chariots themselves. It is known from artistic evidence on pottery that the sport existed in the Mycenaean world, but the first literary reference to a chariot race is one described by Homer, at the funeral games of Patroclus. The participants in this race were Diomedes, Eumelus, Antilochus, Menelaus, and Meriones. The race, which was one lap around the stump of a tree, was won by Diomedes, who received a slave woman and a cauldron as his prize. A chariot race also was said to be the event that founded the Olympic Games; according to one legend, mentioned by Pindar, King Oenomaus challenged suitors for his daughter Hippodamia to a race, but was defeated by Pelops, who founded the Games in honour of his victory.