Arrhidaeus was the son of Philip II and the half-brother of Alexander the Great. He had limited capacity to rule and was sidelined during Alexanderโs life.
After Alexanderโs death, rival generals agreed to crown him as Philip III to maintain Argead legitimacy, but he ruled only under regents like Perdiccas and Antipater.
Power struggles among the Diadochi made him a pawn; Olympias later captured and executed him in 317 BC to clear the path for her faction.