Alexander was perhaps the greatest conquering general in history. In just over a generation, his northern Greek state of Macedon rose to control the whole of the vast Persian Empire. It was the legacy of his father, Philip, that launched Alexander on a spectacular career of conquest that planted Hellenic culture across most of Asia. In a dozen years Alexander took the whole of Asia Minor and Egypt, destroyed the once mighty Persian Empire, and pushed his army eastwards as far as the Indus. No-one in history has equaled his achievement. Julius Caesar, contemplating his hero's statue, is said to have wept because by contrast he had accomplished so little.
Much of Alexander's success can be traced to the Macedonian phalanx, a close-ordered battle formation of sarissa-wielding infantry that proved itself a war-winning weapon. The army Alexander inherited from his father was the most powerful in Greece, highly disciplined, trained and loyal only to the king. United in a single purpose, they fought as one. Alexander recognized this and is quoted as saying, "Remember upon the conduct of each depends the fate of all." Cavalry was also of crucial importance in the Macedonian army, as the driving force to attack the flanks of the enemy in battle. A talented commander, able to anticipate how his opponent would think, Alexander understood how to commit his forces to devastating effect, and was never defeated in battle. He also developed a corps of engineers that utilized catapults and siege towers against enemy fortifications. Alexander led from the front, fighting with his men, eating with them, refusing water when there was not enough, and his men would quite literally follow him to the ends of the (known) world, and none of his successors was able to hold together the empire he had forged. Although he died an early death his fame and glory persist to this day.
This concise history gives an overview of Alexander's life from a military standpoint, from his early military exploits to the creation of his empire and the legacy left after his premature death.