Alexander I, the true founder of the Macedonian state, is known as “Philhellene”. But, paradoxically, collaboration with the Persians played a crucial rule in his policy. Although Herodotus presents the beginnings of his relations with Persia as a result of the initiative of the Persian commander Megabazus, it seems that Alexander, or his father Amyntas, willingly decided to establish connections with the empire, seeing this as a chance to strengthen their position in Macedonia. Alexander was a loyal ally of Xerxes, but when the Persians had been driven away he used the political vacuum in the region to his advantage. Gathering communities inhabiting the area near Macedonia, he enlarged his realm. The prevalent opinion is that Alexander acquired the byname “Philhellene” as early as the fifth century BC. It seems more probable, though, that it happened much later; at least the first evidence of its use comes from the second century AD. Alexander’s image, highly ambiguous in Herodotus’ Histories, becomes more positive in the rhetoric of the fourth century BC, which emphasised the alleged contributions that Philip II’s ancestor had made to the Greek cause during Xerxes’ invasion. But it seems most probable that Alexander was given his cognomen by scholars of the Hellenistic or Early Roman period.