In their origin the great cities of Babylonia were little more than collections of rude huts constructed at first of reeds cut in the marshes, and gradually giving place to rather more substantial buildings of clay and sun-dried brick. From the very beginning it would appear that the shrine of the local god played an important part in the foundation and subsequent development of each centre of population. Of the prehistoric period in Babylonia we know little, but it may be assumed that, already at the time of the Sumerian immigration, rude settlements had been formed around the cult-centres of local gods. This, at any rate, was the character of each town or city of the Sumerians themselves during the earliest periods to which we can trace back their history. At Fâra, the most primitive Sumerian site that has yet been examined, we find the god Shuruppak giving his own name to the city around his shrine, and Ningirsu of Lagash dominates and directs his people from the first. Other city-gods, who afterwards became powerful deities in the Babylonian pantheon, are already in existence, and have acquired in varying degrees their later characters. Enki of Eridu is already the god of the deep, the shrine of Enzu or Nannar in the city of Ur is a centre of the moon-cult, Babbar of Larsa appears already as a sun-god and the dispenser of law and justice, while the most powerful Sumerian goddess, Ninni or Nanâ of Erech, already has her shrine and worshippers in the city of her choice. By what steps the city-gods acquired their later characters it is impossible now to say, but we may assume that the process was a gradual one. In the earlier stages of its history the character of the local god, like that of his city, must have been far more simple and primitive than it appears to us as seen in the light of its later development. The authority of each god did not extend beyond the limits of his own people's territory. Each city was content to do battle on his behalf, and the defeat of one was synonymous with the downfall of the other. With the gradual amalgamation of the cities into larger states, the god of the predominant city would naturally take precedence over those of the conquered or dependent towns, and to the subsequent process of adjustment we may probably trace the relationships between the different deities and the growth of a pantheon. That Enki should have been the god of the deep from the beginning is natural enough in view of Eridu's position on an expanse of water connected with the Persian Gulf. But how it came about that Ur was the centre of a moon-cult, or that Sippar in the north and Larsa in the south were peculiarly associated with the worship of the sun, are questions which cannot as yet be answered, though it is probable that future excavations on their sites may throw some light upon the subject.