Alexander was the son of King Philip II of Macedonia born approximately on July 20th in 356 BC. His mother was Olympias, a young princess from Epirus. Alexander was a remarkable person who loved to recite Homeric poetry. At age fourteen his father sent him to study science, mathematics, and philosophy with Aristotle of Stagira. Alexander looked up to Aristotle "like a father", and it can later be seen that Aristotle gave Alexander the knowledge it took to be one of the greatest rulers in history. .
Alexander was a man of extremes and contradictions. At times he would have intense spurts of energy and then long sulks. He showed extreme generosity and at the same time murderous cruelty against former friends. One would guess given common knowledge that his insecurities most likely were originated in his childhood; perhaps the relationship with his father. After the assassination of his father, King Philip II, Alexander was in direct line to take over as ruler. Alexander was to go down in history as the "father of the Hellenic world", "the unopposed leader of the Greek world", and last but not least "the Great", a title given for his numerous victories. .
The mobile elite was Alexander's Companion Cavalry consisting primarily of the cream of the Macedonian aristocracy. The backbone of the army was the phalanx. The phalanx was six infantry brigades, capable of fighting a compilation of different types of warfare, but specializing in set-piece battle in an eight-deep hedgehog formation with five and a half meter-long spears. The phalanx was the main weapon of warfare; yet, there were also specialist units: skirmishers, archers, and light infantry with mountain training. There were also units comprised of non-Macedonian Greeks whom, fighting for Alexander, helped justify Alexander's claim to be the "General in Chief of the army of Hellenes". Alexander's Army also had very important back-up units.