The Battle of Issus occurred in southern Anatolia, in November 333 BC. The invading Macedonian troops, led by Alexander the Great, defeated an army led by Darius III of Achaemenid Persia in the second great battle of Alexander's conquest of Asia. After the Macedonians soundly defeated the Persian satraps of Asia Minor (led by the Greek mercenary, Memnon of Rhodes) at the Battle of the Granicus, Darius took personal command of his army. He gathered reinforcements and led his men in a surprise march behind the Macedonian advance to cut their line of supply. This forced Alexander to countermarch, setting the stage for the battle near the mouth of the Pinarus River and the town of Issus.