Abstract
This article presents a research of the marble stele found on the Cos island by R. Herzog. The stele is one of the most significant testimonies about the religious life at Miletus during the Hellenistic period. This document proclaims the panhellenic status of the Didymeia’s festival and establishes the coronation of the winner. Such transformation of the local festival was aimed at ‘propaganda’ of Apollo Didymeus’ cult among other Greeks. We can see the image of Apollo Didymeus on the coins of Miletus of that period with a new phase of the large Apollo’s temple construction beginning at the same time. All these may reflect the general politics aimed at the expansion of sanctuary’s influence. Inscriptions from Didyma and other sites of the Mediterranean and numismatic data confirm that from the end of the 3rd century BC the influence of the sanctuary and the oracle has spread across the region.