The ancient Olympic Games were originally a festival, or celebration, of and for Zeus; events such as a footrace, a javelin contest, and wrestling matches were added later. The Olympic Games were a series of athletic competitions among representatives of city-states and one of the Panhellenic Games of ancient Greece.
They were held in honor of Zeus, and the Greeks gave them a mythological origin. The first Olympics is traditionally dated to 776 BC. They continued to be celebrated when Greece came under Roman rule, until the emperor Theodosius I stopped them in AD 393 as part of the campaign to make Christianity as the State religion of Rome.
The games were held every four years, or Olympiad, which became a unit of time in historical chronologies.
During the celebration of the games, an Olympic Truce was made so that athletes could travel from their cities to the games in safety. The prizes for the victors were olive leaf wreaths or crowns.
The games became a political tool used by city-states to assert dominance over their rivals. Politicians would announce political alliances at the games, and in times of war, priests would offer sacrifices to the gods for victory.
The games were also used to help spread Hellenistic culture throughout the Mediterranean. The Olympics also featured religious celebrations. The statue of Zeus at Olympia was counted as one of the seven wonders of the ancient world. Sculptors and poets would come together each Olympiad to display their works of art to would-be customers.
The ancient Olympics had fewer events than the modern games, by the time of the Classical Greek culture, in the fifth and fourth centuries BC, the games were restricted to male participants and only freeborn Greek men were allowed to participate, although there were victorious women chariot owners. As long as they met the entrance criteria, athletes from any Greek city-state and kingdom were allowed to participate.
The games were always held at Olympia rather than moving between different locations as is the practice with the modern Olympic Games. Victors at the Olympics were honored, and their feats recorded for future generations.
The only competition held then was the stadion race, a race over about 190 metres (620 feet), measured after the feet of Hercules. The word stadium is derived from this foot race.
(Adapted from Ancient Olympic Games Facts for Kids. Kiddle Encyclopedia. )