Battle of Gaugamela

On 1 October 331 BC, Alexander the Great won the decisive battle of his campaign against the Persian Empire at Gaugamela, near modern Erbil in northern Iraq. King Darius III had gathered an enormous army from across his empire, including war elephants and scythed chariots with blades on their wheels, and chose wide open ground where his larger forces could surround the Macedonians. Alexander had perhaps 47,000 men. He angled his army to the right, drawing Persian cavalry after him and stretching the Persian line. When a gap opened in the Persian center, Alexander led his Companion cavalry in a wedge straight toward Darius. The Macedonian infantry opened lanes to let the chariots pass harmlessly through. As in the Battle of Issus, Darius fled, and the Persian army collapsed, although Alexander's left wing under Parmenion had come under heavy pressure. After the victory, Alexander marched into Babylon and captured the Persian royal capitals of Susa and Persepolis. Darius was murdered by his own nobles the following year. Gaugamela effectively ended the Persian Empire.