Following the Classical period was the Hellenistic period (323–146 BC), during which Greek culture and power expanded into the Near and Middle East from the death of Alexander until the Roman conquest. Roman Greece is usually counted from the Roman victory over the Corinthians at the Battle of Corinth in 146 BC to the establishment of Byzantium by Constantine as the capital of the Roman Empire in AD 330. Finally, Late Antiquity refers to the period of Christianization during the later 4th to early 6th centuries AD, consummated by the closure of the Academy of Athens by Justinian I in 529.