_The common calendar and cycle of festivals_, observed by all Dorians (of which the Carneia was chief), and the distribution in Greece of the worships of Apollo and Heracles, which attained pre-eminence mainly in or near districts historically "Dorian," suggest that these cults, or an important element in them, were introduced comparatively late, and represent the beliefs of a fresh ethnic superstratum. The steady dependence of Sparta on the Delphic oracle, for example, is best explained as an observance inherited from Parnassian ancestors.
_The social and political structure_ of the Dorian states of Peloponnese presupposes likewise a conquest of an older highly civilized population by small bands of comparatively barbarous raiders. Sparta in particular remained, even after the reforms of Lycurgus, and on into historic times, simply the isolated camp of a compact army of occupation, of some 5000 families, bearing traces still of the fusion of several bands of invaders, and maintained as an exclusive political aristocracy of professional soldiers by the labour of a whole population of agricultural and industrial serfs. The serfs were rigidly debarred from intermixture or social advancement, and were watched by their masters with a suspicion fully justified by recurrent ineffectual revolts. The other states, such as Argos and Corinth, exhibited just such compromises between conquerors and conquered as the legends described, conceding to the older population, or to sections of it, political incorporation more or less incomplete. The Cretan cities, irrespective of origin, exhibit serfage, militant aristocracy, rigid martial discipline of all citizens, and other marked analogies with Sparta; but the Asiatic Dorians and the other Dorian colonies do not differ appreciably in their social and political history from their Ionian and Aeolic neighbours. Tarentum alone, partly from Spartan origin, partly through stress of local conditions, shows traces of militant asceticism for a while.
_Archaeological evidence_ points clearly now to the conclusion that the splendid but overgrown civilization of the Mycenaean or "late Minoan" period of the Aegean Bronze Age collapsed rather suddenly before a rapid succession of assaults by comparatively barbarous invaders from the European mainland north of the Aegean; that these invaders passed partly by way of Thrace and the Hellespont into Asia Minor, partly by Macedon and Thessaly into peninsular Greece and the Aegean islands; that in east Peloponnese and Crete, at all events, a first shock (somewhat later than 1500 B.C.) led to the establishment of a cultural, social and political situation which in many respects resembles what is depicted in Homer as the "Achaean" age, with principal centres in Rhodes, Crete, Laconia, Argolis, Attica, Orchomenus and south-east Thessaly; and that this régime was itself shattered by a second shock or series of shocks somewhat earlier than 1000 B.C. These latter events correspond in character and date with the traditional irruption of the Dorians and their associates.