How Alexander the Great Asserted His Authority

Because he was such a force of nature, we tend to think that Alexander the Great’s accession to the throne of Macedon and leadership of Greece came smoothly. In fact, the assassination of Philip II injected considerable chaos into Macedonian politics and in the sphere of influence that mighty king had carved in Greece. Alexander was the most natural successor, but there were other contenders. A power vacuum threatened. Greece would have been happy to break away and Persia would have been happy to fund them in doing so. How, then, did Alexander the Great assert his authority, first over Macedon, and then over Greece?


Alexander started in a good position, as he was not only the oldest son of Philip, but had proven himself on the battlefield at Chaeronea, and so had the loyalty of much of the army. Still, Philip had multiple wives, and after Chaeronea, he married again, to Cleopatra Eurydice. Unlike Alexander’s mother, Olympias, who was from Epirus, Cleopatra was a member of the Macedonian nobility. Any children from such a marriage would therefore be full Macedonian as well.

Alexander had also been briefly exiled by his father after a confrontation famously described by Plutarch:

The disorders in his household, due to the fact that his marriages and amours carried into the kingdom the infection, as it were, which reigned in the women’s apartments, produced many grounds of offense and great quarrels between father and son, and these the bad temper of Olympias, who was a jealous and sullen woman, made still greater, since she spurred Alexander on. The most open quarrel was brought on by Attalus at the marriage of Cleopatra, a maiden whom Philip was taking to wife, having fallen in love with the girl when he was past the age for it. Attalus, now, was the girl’s uncle, and being in his cups, he called upon the Macedonians to ask of the gods that from Philip and Cleopatra there might be born a legitimate successor to the kingdom. At this Alexander was exasperated, and with the words, ‘But what of me, base wretch? Dost thou take me for a bastard?’ threw a cup at him. Then Philip rose up against him with drawn sword, but, fortunately for both, his anger and his wine made him trip and fall. Then Alexander, mocking over him, said: ‘Look now, men! here is one who was preparing to cross from Europe into Asia; and he is upset in trying to cross from couch to couch.’

To make matters worse, Attalus was a senior general in the Macedonian army, who had been stationed with Parmenio, the army’s second-in-command, in Asia Minor. At the time of Philip’s assassination, they had been preparing a bridgehead for the invasion of Persia. It was therefore possible that Attalus could come back to Macedon with his army to press his family’s claim.

Wasting no time after being proclaimed king, Alexander got the support of Antipater, the other senior general in Philip’s army, and began eliminating rival claimants to the throne. Olympias murdered Cleopatra and her daughter by burning them alive, an act which Alexander regretted. Attalus was also assassinated. This became an unfortunate necessity, following such a series of events.

Alexander the Great Olympias
Alexander and Olympias

Alexander’s consolidation of power in Macedon, with the assistance of his mother Olympias, was swift and brutal. It was not unique, either. It did not indicate that Alexander would become “the Great.” Plenty of leaders came to power, and would come to power, in similar ways, and face horrible ends.

Let us turn south to Greece, and see a far more teachable use of power.


Greece had only recently recognized Macedonian hegemony. The death of Philip II, and a power vacuum to follow, was the perfect excuse for a wide revolt. Once Alexander consolidated his authority in the north, he knew he would need to demonstrate it in the south, especially against Thebes and Athens. In fact, Attalus had previously been in talks to defect.

Alexander did not spend time gathering a large army. He wanted this to be over and done with, relying on speed, and surprise.

Taking 3,000 cavalry with him, including some of his crack Companions, Alexander moved south into Thessaly. There, in a pass between Mount Olympus and Mount Ossa, he and his men ran into a Thessalian force which had stationed themselves in opposition. The Thessalians were also skilled horsemen. They would distinguish themselves greatly at the Battle of Gaugamela a few years later. They would be hard to dislodge indeed.

Alexander, however, knew that warfare is not nearly as much of a physical process as it is a mental one. The first thing to attack is your opponent’s mind. This is the essence of Sun Tzu’s supreme excellence of winning without fighting.

Rather than attack them and risk major casualties, or retreat and lose the prestige he needed, Alexander the Great rode around the Thessalians, through some woods and over rough terrain on Mount Ossa, and appeared behind them. When the Thessalians realized what happened, they acknowledged him as their leader, and joined his expedition.

This maneuver was of the type which would define Alexander as “the Great.” Without fighting, he had broken his opponent’s morale and gotten what he wanted. His future maneuvers would use the same principle – attempt to discern the mind of his opponent, and then attack where his weakness lay. If fighting was necessary, it would happen in the most favorable circumstances, even when his army was greatly outnumbered.

Alexander’s next stop was at Thermopylae, even then a hallowed site. There, he gained recognition as leader of the Amphictyonic League, a group of city-states and their associated tribes which had been set up as early as 1100 BC to protect the Temples of Apollo at Delphi (with its oracle) and Demeter at Thermopiles. Leadership of the Amphictyonic League was a prestigious appointment. Philip had enjoyed it before.

Alexander the Great Amphictyonic League

Demosthenes of Athens was the ringleader of the rebellious activity in Greece. Demosthenes, the man who made the term “Philippic” famous, had long been a steadfast opponent of Philip II. In addition to his natural intransigence, Demosthenes had been funded by the King of Persia, a fact Alexander understood all too well. Nevertheless, with his newfound strength, he was prepared to treat the holdouts with magnanimity. Diodorus Siculus explains:

In order to overawe those who refused to yield otherwise, he set out at the head of the army of the Macedonians in full battle array. With forced marches he arrived in Boeotia and encamping near the Cadmeia threw the city of the Thebans into a panic. As the Athenians immediately learned that the king had passed into Boeotia, they too abandoned their previous refusal to take him seriously. So much the rapid moves and energetic action of the young man shook the confidence of those who opposed him.The Athenians, accordingly, voted to bring into the city their property scattered throughout Attica and to look to the repair of their walls, but they also sent envoys to Alexander, asking forgiveness for tardy recognition of his leadership.

Even Demosthenes was included among the envoys; he did not, however, go with the others to Alexander, but turned back at Cithaeron and returned to Athens, whether fearful because of the anti-Macedonian course that he had pursued in politics, or merely wishing to leave no ground of complaint to the king of Persia. He was generally believed to have received large sums of money from that source in payment for his efforts to check the Macedonians, and indeed Aeschines is said to have referred to this in a speech when he taunted Demosthenes with his venality: “At the moment, it is true, his extravagance has been glutted by the king’s gold, but even this will not satisfy him; no wealth has ever proved sufficient for a greedy character.” Alexander addressed the Athenian envoys kindly and freed the people from their acute terror.

Then he called a meeting at Corinth of envoys and delegates, and when the usual representatives came, he spoke to them in moderate terms and had them pass a resolution appointing him general plenipotentiary of the Greeks and undertaking themselves to join in an expedition against Persia seeking satisfaction for the offenses which the Persians had committed against Greece.Successful in this, the king returned to Macedonia with his army.


In a few brief months and with almost no bloodshed in Greece, the young King of Macedon asserted his authority over his father’s most important vassals. Anticipating Julius Caesar, he controlled the news cycle with action. Those who aspire to hegemony must move quickly to demonstrate their worthiness of it once a change of leadership occurs. From the Syrian principalities, which saber-rattled after the death of Thutmose III, to Kim Jong-un’s penchant for testing new Presidents of the United States, players who had been on the margins have always made their bids for greater power.

Yet, these attempts are often disorganized, as they need to react to the new situation as suddenly as the new leader they seek to test. Once Alexander secured his base of power in Macedon (through regrettable means), he wasted no time in asserting his authority in Greece, and filling the vacuum Philip left behind. His rapid movement, demonstrable competence, magnanimity in victory, and charismatic ideals – calling on all Greece to unite in a crusade against the ancient enemy Persia – successfully broke the rebels’ will to fight. Attacking their morale, not their bodies, was Alexander’s primary aim, and this is how he asserted his authority. He gave his enemy no time to get the confidence in themselves to resist him more formidably. Meanwhile, he proved himself a worthy leader to follow.

It would not always be such smooth sailing. Alexander the Great would soon need to venture north to assert his authority over Thrace, and during this time, a more serious rebellion broke out in Thebes. You can read much more about that in chapter 8 of Lives of the Luminaries. It appears exclusively there. Nevertheless, he secured his base of power, setting himself up for things to come.

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