Alexander's royal blood commanded respect but he was not the only prince to enjoy it. In practice the throne had not always passed to the eldest son and the custom that the king should be of royal blood was a hollow one, for barons could hail a royal infant and then rule through him, while many barons could themselves claim the blood of their local royalty. Philip's baby son by Eurydice was one such danger, for barons like his great-uncle Attalus would hope to rule in his name. Although a regency was possible, it was unlikely while other princes of suitable age were alive. Here Alexander's main rival was his cousin Amyntas who had actually been a child heir to the kingdom twenty-three years before. His uncle Philip had been appointed regent and continued to rule as king when he proved his extraordinary powers of conquest and diplomacy, but Amyntas had survived, a man of twenty-five or so when Philip died, and as a sign of continuing favour, he had been married recently to Philip's daughter by an Illyrian mistress. Against Alexander, he had the vital advantage of age and, in so far as rights mattered, a claim to return to the kingship which he had once been too young to inherit. Besides Amyntas there were the highland princes who might lead their tribes to independence; there was, in the last resort, Arrhidaeus, Philip's son by a mistress from Thessaly whom gossip described as a dancing-girl. Clearly, his mother was not royal, and her low birth would diminish his status: he was also halfwitted, and yet it is a fine proof of Alexander's nervousness that several months before Philip's death he feared displacement by this last resort.

As a prelude to his Asian invasion Philip had been approached by the native ruler of Caria, a country far south on the western coast of the Persian empire and invaluable to an invader with a fleet as weak as Philip's. Diplomacy, as usual, was to be sealed by marriage, and Philip had decided to offer his Arrhidaeus to the Carian's daughter: it was as delicate a bargain as all his others, for a half-witted son was a light price for such an alliance, but without Alexander, it would have worked. Just back from his months in voluntary exile, Alexander had not adjusted to the fact of Olympias's divorce. Seeing Arrhidacus's honour as another threat to his inheritance, he had drawn his own friends around him and despatched his friend Thettalus, the famous Greek actor, to plead his cause at the Carian's court; he was no illegitimate idiot, he was a rightful son and heir, so the Carian should accept him in marriage instead. The man had been delighted beyond what he had dared to hope, but news of the offer had reached Philip first, and he had marched into Alexander's quarters, accused him of meddling and exiled the friends who had helped his interference; sensing trouble, the Carian ruler at once took fright and gave his daughter to a Persian aristocrat. A brilliant coup was ruined, because Alexander was nervous and could not understand that his father would never have wasted his heir on a passing Oriental marriage.

The Carian affair showed up Alexander's youth and sounded the first note for the grim discordance that would follow Philip's murder. The sequence of events was familiar enough. Philip and every other Macedonian king had begun their reigns with a family purge of rivals, a customary necessity in any ancient monarchy, whether Persian, Greek, Roman or Egyptian, and one which Alexander would certainly not neglect. Once these palace affairs began to seem settled, the heir would appeal to such commoners and soldiers as were near him; their support was usually a matter of course, and could be used to round off the purging of rivals. No Macedonian king was ever created by the lone fact of his commoners' support; it was worth having, but family and nobles counted for far more. They were never easily won by a younger man.

At the age of twenty, with his young friends in exile, Alexander had shown how he needed more practised support for his inheritance, and at once in the theatre at Aigai it had become clear where it might be found. As his father lay dead, first to declare for him was his namesake Alexander, a prince of highland Lyncestis, who put on his breastplate and followed his chosen king into the palace: here was more than the first sign of highland loyalty, for this Alexander was son-in-law of the elderly Antipater, one of Philip's two most respected officers and enough of a baron to create the new king. Such immediate homage was itself suspicious, and the Lyncestian's link by marriage foundered on other doubts; the sequence of events cannot be dated, but soon after Alexander had been welcomed his two brothers were killed on a charge of sharing in Philip's murder.

Round Lyncestian Alexander, not for the last time, the ties of two Macedonian families seem to have conflicted, until he had to choose between his brothers and his marriage; possibly, his homage was swift because he knew of his brothers' plottings, and yet his link with Antipater's family sufficed to keep him straight. All three brothers were sons of a man with the Lyncestian name of Aeropus, and nearly two years earlier an Aeropus is known to have clashed with Philip and been sent into exile for the trivial offence, it was said, of dallying with a flute-girl instead of appearing on parade. Possibly, two of his sons had sworn revenge for their father but failed to enlist a brother who had married away from them. Instead they may have joined in Pausanias's plot where they perhaps were the men who had waited with his horses: perhaps, but enemies' accusations are never proof of guilt, and the two Lyncestian brothers may have been rivals rather than murderers. To Alexander's supporters the distinction was hardly important; a faint trail of friends and relations suggests that their arrests were as justified as past Macedonian history made them seem.

When Philip died, wrote a biographer four hundred years after the event, 'Macedonia was scarred and looking to the sons of Aeropus together with Amyntas', and Amyntas's past suggests this informed guess may be correct. Amyntas, former child-heir to the kingdom, had recently been married by Philip to a wife who was half Illyrian. This may have helped to link him with the north-western tribe of Lyncestians and like Alexander he could point to a grandmother of Lyncestian blood. Only two more facts can be ascribed to him, both of them tantalizing; at some date, possibly in his early youth, he had probably travelled in central Greece and visited the famous cave of Trophonius, where he would have gone through an elaborate ceremonial before braving the descent to question its oracle and offering a gift, as an inscription suggests, on his own behalf. Remarkably, he was recorded as 'king of the Macedonians', possibly because he had retained his title when Philip supplanted him, possibly because his visit had occurred when Philip was still his regent. He reappears as Macedonian representative for a disputed frontier town, also in Boeotia; this honour was shared by another Macedonian who defected to Persia at Alexander's accession. This coincidence is probably irrelevant to their loyalties in 336 as their joint honour was granted at least two, maybe ten, years earlier. But another dedication from the shrine of the

same frontier town names a Greek contemporary, most probably a general from Thessaly who is known to have fought in Philip's advance force before he too defected to Persia. It is unsound to use these local inscriptions to link the two defectors with 'king' Amyntas. Maybe his friends were the two Lyncestian brothers who championed him, perhaps, as a king more suited to their tribe. But the defectors may have been dislodged differently, perhaps by the next coup, directed against the advance force in which one, maybe two, served. However, another Lyncestian defected too, perhaps the son of one of the suspect brothers. The links, therefore, between Amyntas, the Lyncestians and defection remain unclear, though these Macedonians' willingness to fight against their countrymen is proof of the affair's gravity.