The blended prehistoric civilization, with its epochs checked off in centuries or millennia, and, thanks to the archæologists, to-day rapidly emerging throughout the Greek world in Attica, Bœotia, Asia Minor, the islands and the Peloponnesus, has received not unnaturally, if prematurely, the general name “Mycenæan” from the great royal tombs and smaller graves and the strong walls of Mycenæ and from the rich and amazing treasure recovered from the graves excavated within the Gateway of the Lions. Accumulating evidence has indicated the insufficiency of the term to include both the art and the architecture. Successive periods and various origins must yet be disentangled. But Mycenæ and Tiryns, as being the most impressive in their entirety, continue to represent this prehistoric civilization to the majority of visitors, and the term “Mycenæan” may serve until some happier names are suggested to distinguish at once between the home-bred and the imported. On the borderland between mere shadowy tradition and an approximately exact chronology two events seemed to the Greeks themselves of preëminent importance and were referred by them to the twelfth century B. C.—the Fall of Troy, and the Return of the Heracleidæ, or the Dorian conquest, as we should now describe this movement. Although Thucydides states that “in the eightieth year after the Trojan War the Dorians, led by the Heracleidæ, conquered the Peloponnesus,” it may be found necessary to assume a much longer interval, especially if we allow for a series of Dorian conquests.