Alexander III of Macedon, known as Alexander the Great (21 July 356 BCE – 10 or 11 June 323 BCE), was the son of King Philip II of Macedon. He became king upon his father's death in 336 BCE. He became the king of Persia, Babylon and Asia, and created Macedonian colonies in the region. He named more than 70 cities after himself—and one after his horse. Alexander's conquests spread Greek culture, also known as Hellenism, across his empire. Alexander's reign marked the beginning of a new era known as the Hellenistic Age because of the powerful influence that Greek culture had on other people. Alexander succeeded his father as King Alexander III. He completed the invasion his father had begun, gaining power over the Persian Empire.
The Battle of Gaugamela was the battle of Alexander the Great's invasion of the Persian Achaemenid Empire. He got in a war first with the Achaemenid Persian Empire under Darius III, and then against local warlords as far east as Punjab, India. Alexander the Great was one of the most successful military commanders, he was undefeated in battle. Alexander assumed the kingship of Macedon following the death of his father Philip II. Alexander had already made more plans prior to his death for military and mercantile expansions into the Arabian Peninsula, after which he was to turn his armies to the west. Alexander's diadochi quietly abandoned these grandiose plans after his death. Instead, within a few years of Alexander's death, the Diadochi began fighting with each other, dividing up the Empire between themselves, and triggering 40 years of warfare.