The ancient 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 Olympic Games are traditionally dated to 776 BC.

The games were held every four years, or Olympiad, which became a unit of time in historical chronologies. They continued to be celebrated when Greece came under Roman rule, 2nd century BC.

During the celebration of the games, an Olympic Truce was enacted 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.

The Olympics also featured religious celebrations. The statue of Zeus at Olympia was counted as one of the seven wonders of the ancient world.

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