Following the decline of the Greek city-states, the Greek kingdom of Macedon rose to power under Philip II. Alexander III, commonly known as Alexander the Great, was born to Philip II in Pella in 356 BCE, and succeeded his father to the throne at the age of 20. He spent most of his ruling years on an unprecedented military campaign through Asia and northeast Africa, and by the age of 30, had created one of the largest empires of the ancient world, which stretched from Greece to Egypt and into present-day Pakistan. He was undefeated in battle and is considered one of history’s most successful commanders.

During his youth, Alexander was tutored by the philosopher Aristotle, until the age of 16. When he succeeded his father to the throne in 336 BCE, after Philip was assassinated, Alexander inherited a strong kingdom and an experienced army. He had been awarded the generalship of Greece, and used this authority to launch his father’s military expansion plans. In 334 BCE, he invaded the Achaemenid Empire, ruled Asia Minor, and began a series of campaigns that lasted ten years. Alexander broke the power of Persia in a series of decisive battles, most notably the battles of Issus and Gaugamela. He overthrew the Persian King Darius III, and conquered the entirety of the Persian Empire. At that point, his empire stretched from the Adriatic Sea to the Indus River.

Seeking to reach the “ends of the world and the Great Outer Sea,” he invaded India in 326 BCE, but was eventually forced to turn back at the demand of his troops. Alexander died in Babylon in 323 BCE, the city he planned to establish as his capital, without executing a series of planned campaigns that would have begun with an invasion of Arabia. In the years following his death, a series of civil wars tore his empire apart, resulting in several states ruled by the Diadochi, Alexander’s surviving generals and heirs. Alexander’s legacy includes the cultural diffusion his engendered conquests. He founded some 20 cities that bore his name, the most notable being Alexandria in Egypt. Alexander’s settlement of Greek colonists, and the spread of Greek culture in the east, resulted in a new Hellenistic civilization, aspects of which were still evident in the traditions of the Byzantine Empire in the mid-15th century. Alexander became legendary as a classical hero in the mold of Achilles, and he features prominently in the history and myth of Greek and non-Greek cultures. He became the measure against which military leaders compared themselves, and military academies throughout the world still teach his tactics.

Military Generalship

Alexander earned the honorific epithet “the Great” due to his unparalleled success as a military commander. He never lost a battle, despite typically being outnumbered. His impressive record was largely due to his smart use of terrain, phalanx and cavalry tactics, bold strategy, and the fierce loyalty of his troops. The Macedonian phalanx, armed with the sarissa, a spear up to 20 feet long, had been developed and perfected by Alexander’s father, Philip II. Alexander used its speed and maneuverability to great effect against larger, but more disparate, Persian forces. Alexander also recognized the potential for disunity among his diverse army, due to the various languages, cultures, and preferred weapons individual soldiers wielded. He overcame the possibility of unrest among his troops by being personally involved in battles, as was common among Macedonian kings.

In his first battle in Asia, at Granicus, Alexander used only a small part of his forces—perhaps 13,000 infantry, with 5,000 cavalry—against a much larger Persian force of 40,000. Alexander placed the phalanx at the center, and cavalry and archers on the wings, so that his line matched the length of the Persian cavalry line. By contrast, the Persian infantry was stationed behind its cavalry. Alexander’s military positioning ensured that his troops would not be outflanked; further, his phalanx, armed with long pikes, had a considerable advantage over the Persians’ scimitars and javelins. Macedonian losses were negligible compared to those of the Persians.

At Issus in 333 BCE, his first confrontation with Darius, he used the same deployment, and again the central phalanx pushed through. Alexander personally led the charge in the center and routed the opposing army. At the decisive encounter with Alexander at Gaugamela, Darius equipped his chariots with scythes on the wheels to break up the phalanx and equipped his cavalry with pikes. Alexander in turn arranged a double phalanx, with the center advancing at an angle, which parted when the chariots bore down and reformed once they had passed. The advance proved successful and broke Darius’s center, and Darius was forced to retreat once again.

When faced with opponents who used unfamiliar fighting techniques, such as in Central Asia and India, Alexander adapted his forces to his opponents’ style. For example, in Bactria and Sogdiana, Alexander successfully used his javelin throwers and archers to prevent outflanking movements, while massing his cavalry at the center. In India, confronted by Porus’s elephant corps, the Macedonians opened their ranks to envelop the elephants, and used their sarissas to strike upwards and dislodge the elephants’ handlers.

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