The ancient world that Alexander the Great transformed in his lifetime was transformed once more by his death. The imperial dynasties of his successors incorporated and reorganized the fallen Persian empire, creating a new land empire stretching from the shores of the Mediterranean to as far east as Bactria. In old Greece a fragile balance of power was continually disturbed by wars. Then, from the late third century, the military and diplomatic power of Rome successively defeated and dismantled every one of the post-Alexandrian political structures. The Hellenistic period (c. 323-30 BC)...