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What happened at the Battle of Issus in 333 BCE?

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Alexander the Great Alexander the Great, detail from Alexander and Porus, painting by Charles Le Brun, 17th century; in the Louvre, Paris, France.

The Battle of Issus, fought in 333 BCE, was a decisive conflict during Alexander the Great’s invasion of the Achaemenian Empire. The battle took place on a coastal plain near Issus in present-day southern Turkey, where the Persian army under King Darius III had positioned itself along the Pinarus River, effectively cutting off Alexander’s line of communications.12

Although the Persians held a significant numerical advantage, their forces were constrained by the narrow terrain between the sea and the mountains. Alexander led his cavalry—specifically the Companion cavalry—in a charge that punched a hole through the Persian infantry, aiming directly for Darius. As the Macedonian phalanx routed the Persian mercenaries in the center, the Persian army collapsed into confusion.21

Darius fled the battlefield, leaving his family behind, who were subsequently captured by Alexander. Alexander treated the royal women with chivalrous care and later offered to return them if Darius recognized his claim as lord of Asia, a demand the Persian king refused.123