Alexander the Great: KS3 History Guide

Who was Alexander and where did he come from?

Alexander was born in 356 BCE in Pella, capital of Macedonia — a kingdom north of Greece regarded by the Greek city-states as semi-barbarian. His father, Philip II, had already transformed Macedonia into the dominant power of the Greek world using a revolutionary military formation: the phalanx, in which soldiers called sarissophoroi carried five-metre pikes called sarissas and advanced in tight formations that were nearly impossible to break.

Alexander's mother Olympias was from the royal house of Epirus and reportedly claimed descent from Achilles, the hero of the Iliad. From childhood, Alexander was told — and believed — that he was descended from gods and heroes. His tutor from age thirteen was the philosopher Aristotle, who schooled him in philosophy, medicine, science and rhetoric. These two influences — divine destiny and rational inquiry — sat uneasily together throughout Alexander's life.

How did Alexander conquer the Persian Empire?

When Philip was assassinated in 336 BCE, Alexander was twenty years old. He moved swiftly: executing rivals, reasserting control over restless Greek cities, and then turning east to fulfil his father's planned invasion of the Achaemenid Persian Empire — the largest state the world had yet seen, stretching from Egypt to Central Asia.

The conquest unfolded in three decisive campaigns:

At Gaugamela, outnumbered perhaps three to one, Alexander executed a daring oblique cavalry charge that broke the Persian centre. Darius fled and was later murdered by his own officers. Alexander declared himself King of Persia.

What made Alexander's army so effective?

Alexander's army combined Macedonian discipline with tactical flexibility. His Companion cavalry — heavy horsemen he led personally — were the offensive arm. They exploited gaps created by the phalanx to break through enemy formations. Alexander always placed himself at the decisive point, leading from the front and receiving serious wounds at least three times.

Vocabulary to know:

• Phalanx — a dense formation of spear-carrying infantry
• Companion cavalry — Alexander's elite Macedonian horsemen
• Siege warfare — taking fortified cities using siege towers, rams and catapults
• Logistics — supplying an army on a 5,000 km march; Alexander built supply depots and recruited local populations

Alexander also founded over seventy cities — naming most of them Alexandria — which served as military strongholds, trade centres and outposts of Greek culture. The most famous, Alexandria in Egypt, became the intellectual capital of the ancient world.

How far east did Alexander go?

After Persia, Alexander pushed into Bactria (modern Afghanistan) and then across the Hindu Kush mountains into the Indus Valley — territory no western army had reached. His campaigns in modern Pakistan showed both his determination and the limits of his power: at the Hyphasis River (the Beas in Punjab), his soldiers refused to go further. After eleven years of continuous campaigning, they had reached their limit.

Alexander turned back. He never returned to Macedonia. He died in Babylon in 323 BCE, aged thirty-two, of a fever — probably typhoid, though some ancient sources allege poisoning. He had no clear heir, and his empire was divided among his generals, the Diadochi (successors), triggering forty years of wars.

What was the Hellenistic world?

The kingdoms that emerged from Alexander's empire — Ptolemaic Egypt, the Seleucid Empire in the Middle East, and others — are collectively called the Hellenistic world (from the Greek Hellas, Greece). In these kingdoms, Greek language, culture, art and philosophy blended with local traditions — Egyptian, Persian, Babylonian — producing something genuinely new.

Greek became the common language of educated people across the Middle East and Egypt for centuries. The Hellenistic period lasted until the Roman conquest, and its cultural legacy persisted long after: the New Testament was written in Greek, and Greek philosophical traditions shaped Christian, Islamic and Jewish theology. This is Alexander's most lasting — and most unintended — legacy.

What do historians argue about Alexander?

The sources for Alexander's life pose serious problems. The main ancient accounts — by Arrian, Plutarch and Diodorus Siculus — were written 300 to 500 years after his death, drawing on earlier sources now lost. They often contradict each other and were shaped by their authors' own political contexts.

Historians today disagree about:

• Whether Alexander had a plan to unite Greeks and Persians or simply exploited conquered peoples
• Whether his adoption of Persian dress and customs was wise policy or personal vanity
• Whether his later behaviour — executing his general Parmenion, killing his friend Cleitus in a drunken rage, demanding to be treated as a god — reflects a deteriorating personality or rational statecraft
• Whether the Hellenistic world's cultural mixing was genuine synthesis or Greek cultural domination dressed as tolerance

The question of who benefits from a historical narrative matters here. Ancient Greek writers celebrated Alexander as the pinnacle of Greek civilisation. Persian, Afghan and Indian traditions remember a destructive invader. Both readings are grounded in evidence; neither is complete on its own.

Frequently asked questions

Why did Alexander never lose a battle?

Ancient sources attribute this to his tactical genius, personal courage and the excellence of his army. Modern military historians point to the Macedonian combined-arms system — phalanx and cavalry working together — and Alexander's ability to read a battlefield quickly and exploit moments of weakness. He also had continuous campaigning experience from his teens. However, it is worth noting that the sources were written by admirers; the full picture of setbacks and near-disasters may be incomplete.

What happened to Alexander's empire after his death?

With no adult heir — his son by his Bactrian wife Roxana was not yet born — his generals divided the empire in the Wars of the Diadochi. Ptolemy took Egypt, founding the Ptolemaic dynasty that ended with Cleopatra in 30 BCE. Seleucus took most of the Middle East and Central Asia. Antigonus and his descendants fought for control of Macedonia and Greece. None of the successors ever reunited the empire.

How should Alexander be judged — conqueror or cultural bringer?

This is precisely the kind of question history asks you to weigh for yourself. The case for greatness: he spread Greek philosophy, science and the common Greek language across a vast area, enabling an era of intellectual exchange. The case against: he destroyed the Persian Empire, killed tens of thousands, enslaved conquered populations, and founded his cities for military rather than humanitarian reasons. Most serious historians conclude that both dimensions are real, and that admiring the military achievement does not require endorsing the human cost.

Was Alexander's death really from a fever?

The ancient sources say he fell ill after heavy drinking at a banquet in Babylon and died twelve days later. Modern medical analysis of the symptoms described suggests typhoid fever complicated by other illnesses. A minority of scholars argue for poisoning — a claim that circulated in antiquity — but the evidence is circumstantial. The most parsimonious explanation remains disease in a man who had already been seriously wounded several times and was in a climate unfamiliar to him.

---

Want to practise a KS3 essay question on Alexander as a significant historical figure? Mercator at aitutors.me can help you build and evaluate the argument.