The Battle of Gaugamela, also called the Battle of Arbela, took place in 331 BC between the forces of the Army of Macedon under Alexander the Great and the Persian Army under King Darius III. It was the second and final battle between the two kings, and is considered to be the final blow to the Achaemenid Empire, resulting in its complete conquest by Alexander.
Alexander the Great, victorious over Darius at the Battle of Gaugamela by Jacques Courtois
Account of Alexander's victory over the last Achaemenid king Darius III at the battle of Gaugamela on 1 October 331 BC and his triumphant entry into Babylon, in cuneiform. Babylon, Iraq. British Museum
The Battle of Gaugamela, Jan Brueghel the Elder, 1602
Indian war elephants in the Achaemenid army at the Battle of Gaugamela
The army of the Kingdom of Macedon was among the greatest military forces of the ancient world. It was created and made formidable by King Philip II of Macedon; previously the army of Macedon had been of little account in the politics of the Greek world, and Macedonia had been regarded as a second-rate power.
Hypaspist in light equipment (modern reconstruction by J. Shumate)
Philip II of Macedon - Roman medallion depicting the Macedonian king.
The Alexander Mosaic showing the Battle of Issus; a Roman copy of a Hellenistic painting, c. 100 BC
Coin of Perdikkas II showing a Macedonian cavalryman armed with two long javelins