On 1 October, 331 BCE, Alexander III of Macedon defeated the Persian king, Darius III, for the final time. Determined to crush Alexander after a defeat in 333 BCE, Darius mobilized his army in Gaugamela, Assyria. This site was chosen by Darius because its open terrain perfectly accommodated his vast army, elephants, cavalry and scythed chariots. On receiving intelligence about the size and composition of Darius’ army (as well as traps and obstacles he had placed), Alexander ignored advice to attack at night. Believing that the portents favoured day, Alexander advanced. By the end of Phase 1, Alexander had succeeded in thwarting Darius. The scythed chariots failed to make an impact, with the two Macedonian phalanxes parting to let them through. In Phase 2, Alexander penetrated the Persian line and his reserves deflected an attack on his camp, causing the Persians to retreat. Alexander was now king of all Asia.
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