The sanctuary of Zeus at Olympia lies in the northwest of the Peloponnesus. Archaic bronze records suggest that the sanctuary was at first under the joint control of the surrounding states. By the early Fifth Century, Elis was in complete control. A very early Oracle made the Olympic Games, founded no later than 776 BC, well known. The games were associated with an "Olympic Peace" that protected the participants. Of special importance are the number of official dedications and diplomatic documents that the various communities of the Greek-speaking Mediterranean world set up at the sanctuary during the Archaic and Classical periods.
Dating as early as the 8th Century BC, official dedications commemorating Olympic victors were regularly found set up at Olympia. The athletes and their civic sponsors come from southern Greece, southern Italy and Sicily. The prevalence of the latter reflects the desire of the Greek colonies to maintain contact with the Motherland. Already in the 6th Century treaties of alliance and of peace including the foremost treaty of "Hellenic Alliance" of the late 480s. Copies were set up not only at Olympia but also at the sanctuary at Poseidon and at Delphi. Official honorary inscriptions are not found in this period.
During the Late Classical and Hellenistic periods, official dedications virtually ceased. Note that one important dedication was made by King Philip II, not the state of Macedonia, openly showing his claim to hegemonial power in Greece, and indicating a new practice of dedication concentrating on the ruler, his family and companions. In 338 BC the Macedonian king attained hegemonial power in Greece and politics now centered on his person. Even if Alexander the Great himself did not take any opportunity for self-representation, it was nonetheless of considerable importance to the Greeks to show their loyalty to these rulers. The area represented by the alliances and peace treaties of this period was smaller than had been the case in the 8th to 5th Centuries, referring primarily to communities in the Peloponnesus. Of special importance is the treaty between Rome and Aetolia that was set up at Olympia, demonstrating the reality of Roman power in Greece during the second century BC. A consequence of the uncertain political situation was the more modest use of honorary dedications, referring to kings of minor importance.
During the Roman period, official dedications were essentially honorary inscriptions. Some Roman governors dedicated monuments as signs of Roman victories, suggesting that the sanctuaries of the Greek world continued to be appropriate locations for such statements. Nevertheless, Olympia had apparently lost her political importance; her effective area of contact was limited to the Peloponnesus. Some indications of Olympia's earlier importance may be seen in the honorary monuments set up at Olympia, but coming from communities as far away as Rome, Kos and Smyrna.