In 1977, important excavations were made near Vergina leading to the discovery of a two-chambered royal tomb, with an almost perfectly preserved male skeleton.Manolis Andronikos, the chief archaeologist at the site, along with a number of other archaeologists, decided it was the skeleton of Philip II, but others have disputed this attribution and instead proposed it to be the remains of Philip Arrhidaeus.An opportunity presented itself in 317 BC when Cassander expelled Polyperchon from Macedonia.Eurydice immediately allied herself with Cassander and persuaded her husband to nominate him as the new regent.
He was a son of King Philip II of Macedon by Philinna of Larissa, and thus an elder half-brother of Alexander the Great.
Plutarch was of the view that he became disabled by means of an attempt on his life by Philip II's wife, Queen Olympias, who wanted to eliminate a possible rival to her son, Alexander, through the employment of pharmaka (drugs/spells); however, most modern authorities doubt the truth of this claim., both to protect his life and to prevent his use as a pawn in any prospective challenge for the throne.
After Alexander's death in Babylon in 323 BC, the Macedonian army in Asia proclaimed Arrhidaeus as king; however, he served merely as a figurehead and as the pawn of a series of powerful generals.
He was in Babylon at the time of Alexander's death on 10 June 323 BC. Arrhidaeus was the most obvious candidate, but he was mentally unfit to rule.
A conflict then arose between Perdiccas, leader of the cavalry, and Meleager, who commanded the phalanx: the first wanted to wait to see if Roxana, Alexander's pregnant wife, would deliver a male baby, while the second objected that Arrhidaeus was the closest living relative and so should be chosen king.