The 3rd century saw a decline in the popularity of the games. The victory list of Africanus ends at the Olympiad of 217 and no surviving text of subsequent authors mention any new Olympic victors. Excavated inscriptions show the games continued, however. Until recently the last securely datable winner was Publius Asclepiades of Corinth who won the pentathlon in 241. In 1994 a bronze plaque was found inscribed with victors of the combative events hailing from the mainland and Asia Minor; proof that an international Olympic Games continued until at least 385.
The games continued past 385, by which time flooding and earthquakes had damaged the buildings and invasions by barbarians had reached Olympia. The last recorded games were held under Theodosius I in 393, but archeological evidence indicates that some games were still held.
Source: Wikipedia
