The Rise and Fall of Alexander the Great’s Empire

Alexander the Great is one of the most famous, or infamous, figures in world history. A man who conquered the superpower of his day and forged a massive empire. But the origins of that empire stretch further back than the man himself. To understand Alexander’s success fully, you first need to go back to the reign of his father: King Philip II of Macedon.

When Philip ascended the throne of Macedon in 359 BC, his kingdom consisted of much of what is today northern Greece. Nevertheless, Macedon’s position at that time was a precarious one, surrounded by Thracians to the east, Paeonians to the north and Illyrians to the west, all hostile to Philip’s kingdom. But thanks to a series of shrewd diplomatic moves and military reforms, he was able to reverse his kingdom’s flailing fortunes. 

Over the course of his 23 year reign, he transformed his kingdom from a backwater of the Hellenic world into the dominant power in the Central Mediterranean. By 338 BC, following his victory at the Battle of Chaeronea against a coalition of Greek city-states that included Athens and Thebes, Philip’s Macedonian Empire theoretically stretched from the borders of Laconia in the south to the Haemus Mountains in modern day Bulgaria. It was this vital, imperial base that Alexander would build on.

Expansion

Philip was assassinated in 336 BC; succeeding him to the Macedonian throne was the teenage Alexander. During his first years in power, Alexander consolidated Macedonian control on the Greek mainland, razing the city-state of Thebes and marching his armies beyond the Danube River. Once these matters were settled, he embarked on his most famous military venture – crossing the Hellespont (today’s Dardanelles) and invading the Persian Empire – the SUPERPOWER of the time. 

‘Alexander Cuts the Gordian Knot’ (1767) by Jean-Simon Berthélemy

Image Credit: Jean-Simon Berthélemy, Public domain, via Wikimedia Commons

At the core of Alexander’s army were two key components. The Macedonian heavy infantry, trained to fight in large phalanx formations, with each soldier wielding a massive, 6 metre long pike called a sarissa. Working in tandem with the heavy infantry on the battlefield were Alexander’s elite, shock ‘Companion’ Cavalry – each equipped with a 2 metre lance called a xyston. And alongside these central units, Alexander also took advantage of some stellar, allied forces: javelinmen from the Upper Strymon Valley, heavy cavalry from Thessaly and archers from Crete.

Backed by this army, slowly Alexander made his way east – gaining significant victories at the River Granicus, Halicarnassus and Issus between 334 and 331 BC. 

By September 331 BC, following a series of bloody battles and large-scale sieges, Alexander had conquered the western provinces of the Persian Empire. His forces commanded most of Anatolia, the Eastern Mediterranean seaboard and the wealthy, fertile land of Egypt. His next move was to continue east, towards ancient Mesopotamia and the heartlands of the Persian Empire.

He decisively defeated the Great Persian King Darius III at the Battle of Gaugamela – on 1 October 331 BC – paving the way for Alexander to take control of the Persian Empire’s key administrative centres: first Babylon, then Susa, then Persepolis in Persia itself and, finally, Ecbatana. With this, Alexander had indisputably conquered the Persian Empire, an achievement that was cemented in mid 330 BC, when the fugitive Darius was assassinated by his former subordinates.

If there had been a different outcome to the Battle of Granicus, we might never have heard about Alexander the Great. Taking place in 334 BC, this was his first major victory against the Persian Empire. Tristan is joined by historian and novelist Adrian Goldsworthy to discuss Alexander and his tactics right at the beginning of his campaign.

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Zenith

The Persian Achaemenid Empire was no more. But nevertheless, Alexander’s campaigning would continue. He and his army ventured further east. Between 329 and 327 BC, Alexander experienced the hardest military campaigning of his life in modern day Afghanistan and Uzbekistan, as he tried to quell Sogdian / Scythian opposition to his rule there. Finally, after agreeing to marry the daughter of a prominent Sogdian chief, Alexander deposited a hefty garrison on this far-flung frontier and continued southeast, across the Hindu Kush into the Indian Subcontinent. 

Between 326 and 325, Alexander extended the Macedonian Empire along the banks of the Indus River Valley, his soldiers being unwilling to march any further east following a mutiny at the Hyphasis River. During his Indian Campaign, Alexander famously confronted King Porus at the Battle of the Hydaspes River. But the struggle continued far beyond this pitched battle, and during one subsequent siege, Alexander suffered a serious wound when an arrow punctured one of his lungs. A close call, but ultimately Alexander survived.

Finally, having reached the mouth of the Indus River, Alexander and his army returned west, to Babylon. Although not before they suffered a gruelling trek across the inhospitable Gedrosian Desert.

Alexander Mosaic, House of the Faun, Pompeii

Image Credit: Berthold Werner, Public domain, via Wikimedia Commons

By the time Alexander the Great died on 11 June 323 BC, his empire theoretically stretched from northwest Greece in the west to the Pamir Mountains and the Indian Subcontinent in the east – it was one of the largest empires the world had yet seen. On his travels, Alexander famously founded several new cities, most of which he named….after himself. Not that he hogged all the glory, he did also supposedly name one after his favourite horse Bucephalus and another after his dog, Peritas. 

Yet of all the cities he founded, today one is more famous than all the rest: Alexandria in Egypt.

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Alexander’s death in 323 BC caused immediate chaos throughout his empire. He died without a designated heir and following a bloody power struggle in Babylon, his former subordinates quickly began carving up the empire amongst themselves in an agreement called The Babylon Settlement. Alexander’s lieutenant Ptolemy, for instance, received control of the rich, wealthy province of Egypt.

The unstable nature of this new Settlement was quickly visible however. Soon, revolts had broken out across the length and breadth of the empire and within 3 years, the first great Macedonian civil war – the First War of the Successors – had also erupted. Ultimately a new settlement was drawn up at Triparadeisus in 320 BC, but this too was soon obsolete. 

Alexander the Great’s untimely death at Babylon in 323 BC triggered an unprecedented crisis across his continent-spanning empire. Within a couple of days, the very chamber in which he died witnessed a gore-soaked showdown between his previously united commanders and soldiers. Within a fortnight, Babylon saw the first siege of the post-Alexander age. In this episode, Tristan Hughes brings to life the imperial implosion that was the immediate aftermath of the Macedonian king's death.

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Ultimately, over the following few tumultuous decades – as power hungry individuals vied for as much land and authority as possible during these violent Wars of the Successors – the Hellenistic Kingdoms began to emerge: the Ptolemaic Kingdom in Egypt, the Seleucid Empire in Asia and the Antigonid Kingdom in Macedonia. Further kingdoms would emerge from the ashes of Alexander’s empire in due course, such as the extraordinary yet enigmatic Greco-Bactrian kingdom in modern day Afghanistan and the Attalid Kingdom in western Anatolia.

It would be these remarkable Successor Kingdoms that would have to face the rise of the next great power in the ancient Mediterranean: Rome.