Following the unification of the multiple city-states of ancient Greece under the rule of his father, Philip II of Macedon (a labour Alexander had to repeat because the southern Greeks rebelled after Philip's death), Alexander conquered the Achaemenid Persian Empire, including Anatolia, Syria, Phoenicia, Judea, Gaza, Egypt, Bactria, and Mesopotamia, and extended the boundaries of his own empire as far as Punjab, India.
Prior to his death, Alexander had already made plans for military and mercantile expansions into the Arabian peninsula, after which he was to turn his armies to the west (Carthage, Rome, and the Iberian Peninsula). His original vision had been to the east, though, to the ends of the world and the Great Outer Sea, as described by his boyhood tutor Aristotle.
Alexander integrated many foreigners into his army, leading some scholars to credit him with a "policy of fusion." He also encouraged marriages between his soldiers and foreigners; he himself went on to marry two foreign princesses.
Alexander died after twelve years of constant military campaigning, possibly as a result of malaria, poisoning, typhoid fever, viral encep...