The Phrygian helmet worn by Alexander on his own Porus Medallions is the most authentic case.

A similar helmet was found in his father’s tomb.

Such helmets are also worn by other Macedonians in contemporaneous tomb friezes.

Macedonian cavalrymen also wore Boeotian helmets.

And hybrids exist.

Alexander also seems to have owned a helmet imitating the Nemean lionscalp of his putative paternal ancestor Heracles. He wears it on the Alexander sarcophagus, probably in the Battle of Issus.

and also in some other early portrait sculptures.