Cleopatra of Egypt is one of history's most famous rulers, but who was responsible for founding the Ptolemaic dynasty from which she came, how, and when? For the answers we go back 300 years before Cleopatra's time, to Ptolemy of Macedonia. He was a friend of Alexander the Great, fighting with him in the epic battles and sieges, which toppled the Persian Empire, and after Alexander's death taking over Egypt after the dead king's commanders carved up his vast empire among themselves. They were soon at war with each other, the co-called Wars of the Successors, as each man fought to increase his share of the spoils. They made and broke alliances with each other cynically and effortlessly, with Ptolemy showing himself no different from the others. But unlike them he had patience and cunning that arguably made him the greatest of the Successors. He built up his power base in Egypt, introduced administrative and economic reforms that made him fabulously wealthy, and as a conscious imperialist he boldly attempted to seize Greece and Macedonia and be a second Alexander. As well as his undoubted military prowess, Ptolemy was an intellectual. He founded the great Library and Museum at Alexandria, making that city the intellectual center of the entire Hellenistic age, and even patronized the mathematician Euclid. Ptolemy ruled Egypt first as satrap and then as its king and Pharaoh for forty years, until he died of natural causes in his early eighties. On his death, his son, Ptolemy II, succeeded him, and the Ptolemaic dynasty was thus established. It was the longest-lived of all the Hellenistic dynasties, falling with Cleopatra three centuries later. As a king, soldier, statesman, and intellectual, Ptolemy was one of a kind, but, unlike Alexander, he never forgot his Macedonian roots. Against all odds, Ptolemy fought off invasions, invaded opponents' territories, and established an Egyptian empire, making his adopted country a power with which to be reckoned. His achievements shaped both Egypt's history and that of the early Hellenistic world.