140 A Short History of The World into Asia upon this long premeditated adventure. But he never followed it. He was assassinated ; it is believed at the instigation of his queen Olympias, Alexander's mother. She was jealous because Philip had married a second wife. But Philip had taken unusual pains with his son's education. He had not only se- cured Aristotle, the greatest philosopher in the world, as this boy's tutor, but he had shared his ideas with him and thrust military experience upon him. At Chaeronia Alexander, who was then only eighteen years old, had been in command of the cavalry. Aiad so it was possible for this young man, who was still only twenty years old at the time of his accession, to take up his father's task at once and to proceed success- fully with the Persian adventure. In 334 B.C. — for two years were needed to establish and confirm his position in Mace- donia and Greece — ^he crossed into Asia, de- feated a not very much bigger Persian army at the battle of the Granicus and captured a number of cities in Asia Minor. He kept along the sea coast. It was necessary for him to reduce and garrison all the coast towns as he advanced because the Persians had control of the fleets of Tyre and Sidon and so had command of the sea. Had he left a hostile port in his rear the Persians might have landed forces to BUST OF ALEXANDER THE GREAT (As in the British Museum)
