Among the surviving creations of Greek religious art the figure of Poseidon is not one of the first importance, perhaps owing to the accident of loss, as we know it was occasionally the theme of the great sculptors and painters. In the anthropomorphic imagination of Homer, the two brother divinities, Zeus and Poseidon, were characteristically distinguished; the latter is marked by a certain ruggedness and violence in demeanour and action, as if his divinity, stately as it appears at times, was usually the manifestation of physical rather than mental power. There is a subtle expression of this distinction in the lines that speak of the countenance and eyes as the salient features of Zeus, but the broad chest as Poseidon's. It is probable that the same idea dominated the types of the advanced periods of art, while a close resemblance was always maintained between the forms of the two personalities. The archaic age could only distinguish them by means of external symbols or inscriptions. The most interesting representations of Poseidon belonging to the art of the sixth century are among the ex-voto terracottas from Corinth in Berlin, some representing him in peaceful attitudes, either driving in a chariot with Amphitrite or standing by her side in hieratic pose before Hermes, holding a tunny-fish and trident (Pl. iii a); one in violent action charging with the trident (Pl. iii b), as we see him, also in a dedicatory bronze of nearly the same period from Chalkis, now in Berlin.

The study of the Poseidon-cult in Hellas is of more value for the Greek historian than for the student of the higher religions of mankind. It lacks the spiritual and ethical interest of some of the Olympian cults, and from the earliest to the latest period Poseidon remains comparatively a backward god, never intimately associated with the nation's intellectual advance. But the ritual presents us with certain facts of great interest. And early Greek ethnography and the history of the earliest migrations of Hellenic tribes can gather much from a minute inquiry into the diffusion of this worship. Modern historians have become accustomed to use the facts of Greek religion as a clue for their researches into the period that precedes recorded history. But the criterion is often misapplied, and the value of it is still occasionally ignored. Much has still to be done in this branch of inquiry, and much may be effected if the evidence is severely scrutinized according to some fixed principles of criticism, and at the outset of this chapter it may be well to state and consider some of these. The historian of the earliest period, if he believes that he can extract anything from the religion and the mythology, has to reckon with three sources of possible evidence: with cult and ritual, with myth pure and simple, and finally with genealogical tables. Now the value of these sources is by no means equal.

The literary records of this cult are in some respects fuller and more explicit than the monuments, and some of the more interesting aspects of the Demeter-Persephone service lack, or almost lack, monumental illustration. The theriomorphic conception, of which we detected a glimpse in the Phigalean legend, can scarcely be said to have left a direct impress upon art; and it is doubtful if even the later aniconic period has left us any representation or ἄγαλμα to which we may with certainty attach Demeter's name. On a few late coins of certain Asia Minor states, of which the earliest is one struck under Demetrius III of Syria in the first century b. c., we find a very rude semblance of a goddess with corn-stalks but with only faint indication of human form. But in spite of the emblems we cannot say that this is a genuine Demeter; it may very probably be merely one of the many forms of the great mother-goddess of Asia Minor, the divine power of fertility and fruits; and it may descend from the same stratum of cult as that to which the type of the Ephesian Artemis belongs, to which it bears an obvious resemblance. Only when Demetrius took it as his badge, he and his people may have regarded it as Demeter's image for his name's sake.

The worship to which this chapter is devoted is one of the most important and fascinating in the whole Hellenic religion. In the study of it we seem to have a picture revealed to us in outline of the early agrarian life, of the social usages on which the family was based, and also of the highest religious aspirations of the people. The folk-lorist and the student of primitive anthropology can gather much from it; and it also contributes largely to our knowledge of the more advanced religious thought in Europe. The primitive element in it is bright and attractive, there is scarcely a touch of savagery, and it is connected at many points with the higher life of the state. The mythology of the cult enthralled the Hellenic imagination and inspired some of the noblest forms of art, and it appeals to the modern spirit with its unique motives of tenderness and pathos, with the very human type of the loving and bereaved mother.

The attempt to explain the name Demeter has been only partly successful: there can be little doubt but that the latter part of the word means ‘mother,’ and this is a fact of some importance, for it shows that the name and the worship is a heritage of the Aryan population, and its universality in Greece gives evidence against the theory that the presence of the female divinity betrays the non-Aryan stock.

The monumental evidence, which always supplements the literary record of the higher Greek cults and often reveals religious facts that might otherwise have escaped our knowledge, is disappointingly meagre as regards Poseidon's worship. But though it may convey to us no new ideas serviceable for the history of this religion, it is useful as illustrating the prevalence of certain cult-concepts which the literature has brought to our notice.

The art-symbolism that attached to him was mainly intended to express the functions and character of the sea-divinity. But the ancient and independent aspect of him as the horse-god is attested by coins and other monuments of some antiquity. Besides those that have been already mentioned we can quote the early coin-device of Potidaia, the fifth-century coins of Rhaukos in Crete, with their fairly prevalent type of Poseidon Hippios, and their combination of the horse's head, trident, and dolphin (Coin Pl. A, 2); also certain sixth-century terracotta pinakes from Corinth in Berlin, on some of which Poseidon appears driving a chariot with Amphitrite, and on one as a horseman of rather diminutive figure (Pl. I a). And the monuments of the later Corinth that arose upon the ruins of the old were full of reminiscences of this traditional cultfigure, which has also inspired several representations of secular art.