In 776, Lykoyrgos of Sparta and Iphitos of Elis organized the Olympic Games in honor of Zeus and instituted a sacred ekecheiria, or truce. After that, the festival acquired a truly national character.
The sanctuary began to grow and develop from the Archaic period, with the first monumental buildings constructed during this time – the temple of Hera, the Prytaneion, the Bouleuterion, the treasuries, and the first stadium.
During the Classical period, the enormous temple of Zeus was also built, alongside many other significant buildings.
Overall, the sanctuary managed to survive the first years of Christian rule under Constantine, with the last Olympic Games being held in 393 BC before Theodosius banned all pagan festivals. In 426 BC, Theodosius II ordered the destruction of the sanctuary.
The site was discovered in 1766, however, the excavations began much later, in 1829, when the French archaeologists of the “Expedition Scientifique de Morée” arrived on the site of the sanctuary at Olympia on 10 May 1829.