Upheaval. Following the collapse of the Mycenaean civilization around 1200 B.C.E., Greece entered a period known as the "Dark Ages." All the great achievements of mainland Greek civilization vanished: the art of writing was lost; centralized government broke down; population declined drastically; and settlements devolved into isolated farming communities. Although some archaeologists are finding evidence for more prosperity, social complexity, and organization than they had previously expected, there is no disputing that this was a time of drastic reorganization of political and economic life in Greece. For one thing, the upheaval at the end of the Bronze Age (3000-1100 B.C.E.) disrupted the networks of exchange from which the Mycenaeans had profited, and Greece became more isolated from the outside world. At the same time, there occurred in this period the first recorded large-scale migrations of people...