As I pointed out in my Hibbert Lectures, Babylon must have been a colony of Eridu. Its tutelary god was a son of Ea of Eridu, and had been worshipped at Eridu long before his cult was carried northward to Babylon. Dr. Peters has since suggested that Ur was similarly a colony of Nippur. The moon-god of Ur was the son of the god of Nippur, and though Ur lay but a few miles from Eridu, it was an inland and not a maritime town. It stood on the desert plateau to the west of the Euphrates, overlooking the Babylonian plain, which at the time of its foundation had doubtless not as yet been reclaimed. But its situation exposed it to Arabian influences. Unlike the other great cities of Babylonia, it was in Arabia rather than in Babylonia, and its population from the outset must have contained a considerable Arabian element. Semitic settlers from Southern Arabia and Canaan occupied it, and it was known to them as Uru, "the city" _par excellence_.(206)
Nippur and Eridu were already old when Ur first rose to fame. They were both great sanctuaries rather than the capitals of secular kingdoms. The god of Nippur was El-lil, "the lord of the ghost-world,"(207) the ruler of the spirits, whose abode was beneath the earth, or in the air by which we are surrounded. He was the master of spells and incantations, of the magical formulæ which enabled those who knew them to keep the evil spirits at bay, or to turn their malice against an enemy. Nippur was peculiarly the home of the darker side of Babylonian religion; the teaching and influences that emanated from it regarded the spirit-world as a world of night and darkness, peopled by beings that were, for the most part, hostile to man. The _lil_ or ghost belonged to the realm of the dead rather than to that of the living, and the female _lilîtu_ was the ancestress of that Lilith whom the Jewish Rabbis made a vampire under the form of a beautiful woman, who lived on the blood of the children she slew at night.
Eridu, on the contrary, was the seat of the Chaldæan god of culture. Ea, whose home was in the deep, among the waters of the Persian Gulf, had there his temple, and it was there that he had taught the first inhabitants of Babylonia all the elements of civilisation, writing down for them the laws they should obey, the moral code they should follow, and the healing spells that prevented disease and death. He was the author of all the arts of life, the all-wise god who knew the things that benefited man; and his son and minister Asari, who interpreted his will to his worshippers, received the title of him "who does good to mankind." While El-lil of Nippur was the lord and creator of the spirit-world, Ea was the lord and creator of men. He had made man, like a potter, out of the clay, and to him, therefore, man continued to look for guidance and help.