The _Iliad_ and the _Odyssey_, however, if they are to be correctly interpreted, must be studied in the light of sociological analogy and archaeological research. Everyone is now familiar with the differentiation which the learning and genius of Ridgeway first defined in the population of early Greece, and with the distinction which he has indicated between the _Achaeans_ and the _Pelasgians_.[51] In Homer, the peoples of Greece are called _Achaeans_: but Ridgeway holds that the Achaeans were not Greeks: that they were not even members of any Mediterranean race; that they were Celts[52] from Central Europe who descended slowly into Greece, who conquered the inhabitants by virtue of superiority in the arts and weapons of war, who settled and intermarried with native royal families, and who, in the course of two hundred years, had become assimilated to the natives in language and culture, until they lost all consciousness of difference.[53] Homer, the poet of the Achaeans, called the Greek-Achaean host, the mixed army of Pelasgians and Achaeans, by a name which belonged only to the Celtic kings in whose courts he sang his songs of praise. The Celtic Achaeans have lost their language but retained their name. The Pelasgians, according to Ridgeway,[54] spoke in the time of Homer an Aryan tongue so well that even their conquerors came to speak it and forgot their own. Yet they were not, in origin, an Aryan race! On this point we find it difficult to agree with Ridgeway, though we admire the scientific reasoning and the profound learning which support his theory. The precise nature of the social organisations of early Greece, Ridgeway does not attempt to decide—at least in his ‘Early Age of Greece’: but we infer from an article which he has written on Homeric land-tenure[55] that he believed, as does Mr. H. Seebohm,[56] that both Achaeans and Pelasgians were tribal peoples.