Key takeaways
- Wikipedia gives Alexander's life as 20/21 July 356 BC to 10/11 June 323 BC; he became king of Macedon in 336 BC at the age of 20.
- He crossed into Asia in 334 BC and defeated Persian armies at the Granicus, at Issus in 333 BC and at Gaugamela in 331 BC.
- His army mutinied at the Hyphasis (Beas) River, which Wikipedia calls the easternmost extent of his conquests.
- He died in Babylon aged 32 with no obvious heir; Wikipedia says some 40 years of war among the Successors followed.
- Every account by people who knew him is lost; the surviving narratives, from Diodorus to Arrian, were written centuries later.
- Ancient writers disagree even on his death: Plutarch describes a fever, Diodorus pain after a bowl of unmixed wine.
Alexander the Great was king of Macedon from 336 BC until his death in 323 BC, and in those thirteen years his army overthrew the Persian Empire and marched as far as the Punjab. Wikipedia describes him as undefeated in battle. This guide puts his reign in order, year by year, then looks at two things a bare list hides: how thin the contemporary evidence is, and how quickly the empire came apart.
Before Asia: Macedon, Philip and Thebes
Alexander was born in Pella, the Macedonian capital. Wikipedia gives the date as the sixth day of the month Hekatombaion, which probably corresponds to 20 July 356 BC, while noting the exact date is uncertain. His father was Philip II; his mother was Olympias of Epirus. Aristotle tutored him until the age of 16.
Philip had turned Macedon, in the words of the Livius.org entry by Jona Lendering, from a backward kingdom into a strong state with a powerful army, and was planning war on Persia when he was murdered in 336 BCE. Alexander succeeded at 20 and inherited the war. In 335 BC he campaigned in the Balkans and then destroyed Thebes, after which he took over leadership of the League of Corinth that his father had created.
The campaigns in order
| Year (BC) | Event |
|---|---|
| 334 | Crosses the Hellespont; victory at the Granicus; Sardis surrenders; siege of Halicarnassus |
| 333 | Defeats Darius III at Issus (November, per Livius) |
| 332 | Captures Tyre after a long siege, then Gaza; enters Egypt |
| 331 | Leaves Egypt; defeats Darius at Gaugamela; takes Babylon and Susa |
| 330 | Winter at Persepolis, sacked in the spring (Livius); Darius later killed by men of his satrap Bessus |
| 329–327 | Central Asia: Bessus executed, Sogdian revolt under Spitamenes, marriage to Roxana |
| 326 | Defeats Porus at the Hydaspes; army mutinies at the Hyphasis (Beas) |
| 324 | Reaches Susa after crossing the Gedrosian Desert; afterwards, mutiny at Opis |
| 323 | Dies in Babylon, 10 or 11 June |
The table follows Wikipedia's article, with Livius used as a cross-check. They differ in small ways: Wikipedia has Alexander advancing on Egypt "in later 332 BC", while Livius says he added Egypt "early in 331". A gap of a few months like this is a reminder that these dates are reconstructed from writers who lived long afterwards, as the section on sources below explains.
Two moments in the list carry more weight than the rest. At Issus, Darius fled and left behind his family; when he offered land and a ransom of 10,000 talents, Alexander replied, according to Wikipedia, that as king of Asia he alone decided territorial divisions. Gaugamela, Wikipedia says, "would be the final and decisive encounter between the two". Persia's own administrative record, the subject of how Achaemenid Persia was governed, shows what Alexander was inheriting, and the Iranologist Pierre Briant, quoted by Wikipedia, suggests Alexander "may therefore be considered to have acted in many ways as the last of the Achaemenids".
The turn at the Beas, and a worked age calculation
East of Porus's kingdom lay the Nanda Empire of Magadha. Wikipedia reports that the army, fearing more large armies and exhausted after years of campaigning, mutinied at the Hyphasis (Beas), which therefore marks the easternmost extent of the conquests. India's own history in the following generation is covered in the Maurya and Gupta empires compared.
Alexander's age at death is a small trap. Both dates are BC, so subtraction works directly: 356 − 323 = 33. But he was born around 20 July and died on 10 or 11 June, a few weeks short of his birthday, so he was 32 — the age Wikipedia gives. From the crossing into Asia in 334 BC to his death is 334 − 323 = 11 years.
Lost eyewitnesses and later historians
Wikipedia's historiography section is blunt: apart from a few inscriptions and fragments, every text written by people who knew Alexander is lost. His campaign historian Callisthenes, his generals Ptolemy and Nearchus, the officer Aristobulus and the helmsman Onesicritus all wrote accounts, and none survives. What we read are later works built on them:
- Diodorus Siculus, 1st century BC
- Quintus Curtius Rufus, mid-to-late 1st century AD
- Arrian, 1st to 2nd century AD
- Plutarch, 1st to 2nd century AD
- Justin, as late as the 4th century
Wikipedia notes Arrian is generally considered the most reliable because he used Ptolemy and Aristobulus, closely followed by Diodorus. The gap shows when the writers disagree. On his death, Plutarch describes a fever after a night of drinking; Diodorus describes pain after a large bowl of unmixed wine and eleven days of weakness, with no fever. Livius adds that for Gaugamela the only contemporary source is a Babylonian Astronomical Diary. Working through problems like this is the method in how we know what historical figures did.
No heir, forty years of war
Alexander had no obvious or legitimate heir; his son Alexander IV was born after his death. The ancient writers disagree here too. Diodorus, as Wikipedia reports him, has Alexander answer "to the strongest" when asked on his deathbed who should inherit; Arrian and Plutarch said he was speechless by then, which implies the story is apocryphal. Diodorus, Curtius and Justin also give what Wikipedia calls the more plausible story, that he handed his signet ring to Perdiccas.
His half-brother Philip III and the infant Alexander IV became joint kings in name only. After Perdiccas was assassinated in 321 BC, Wikipedia says 40 years of war among the Successors (Diadochi) followed, until three blocs emerged: Ptolemaic Egypt, Seleucid Syria and Persia, and Antigonid Macedonia. Both kings were murdered along the way. The Ptolemaic line ended with the queen discussed in Cleopatra beyond the legend.
The EBSCO Research Starter on Alexander, by Clark G. Reynolds, credits his tactics at the Granicus, Issus and Gaugamela, and Wikipedia notes he founded more than twenty cities, the most prominent being Alexandria in Egypt. His death marks the conventional beginning of the Hellenistic period. Athens, whose system is described in Athenian democracy, had already been beaten by Philip and the young Alexander at Chaeronea, the battle Wikipedia dates to 2 August 338 BC.
Placing Alexander next to his neighbours
World History Timeline Sim, our own app, arranges major events chronologically and lets you browse by year, era, region, country or category, and its world history map shows where events took place, which suits a reign that moved across so much ground. Time Travel Mode offers decisions at turning points, but its consequences are simulations, not what happened. The app is free on Google Play with ads and optional in-app purchases; it is built for curiosity-led learning and pairs with coursework rather than replacing it, so Arrian and the other ancient narratives remain the place to check a detail. Related apps sit in the education and brain training category.
Good to know
Frequently asked questions
What did Alexander the Great conquer, in order?
How old was Alexander the Great when he died?
Why did Alexander the Great turn back from India?
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Sources
- Alexander the Great (opens in a new tab)Wikipedia — accessed
- Alexander the Great (opens in a new tab)Livius.org (Jona Lendering) — accessed
- Alexander the Great (Research Starter) (opens in a new tab)EBSCO — accessed
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