Babylonian religion as we first see it is in the form of local cults. Each city with its surrounding district had its own god, whose authority was supreme. Thus Anu was worshipped in Erech, Bel in Nippur, Ea in Eridu, Sin in Uru, Shamash in Larsa and Sippar. When these cities began to be welded together into political systems, the gods also were put together into an organised pantheon in which political situations influenced the relations the gods were made to bear to each other. Thus when Babylon became the capital of the empire its special god, Marduk, became leader among the gods.
A second characteristic feature of the Babylonian religion is that it is based on natural phenomena. The myths are nature myths. The story of the original creation was in a way the prototype of what happened every year. The earth is covered with water from the winter rains (state of chaos). The spring sun (Marduk) fights with and overcomes the water (Tiamat); the earth appears, green things of all kinds and life are produced. The story of the flood may have referred to the annual inundation, with perhaps the added element of severe winds and a tidal wave from the south. Such inundations have occurred in historic times. Ishtar’s descent into the lower world marks the autumn when everything is dry and has been burned up by the fierce summer sun. Ishtar goes to seek the water of life, which in the Babylonian world was a most appropriate metaphor, because water actually was the life of the country. Without it the land was arid and desolate as to-day; with it, its luxuriant vegetation caused the region about Babylon to be called the garden of the gods (Karaduniash).
The creation legend as we have it must have been written after the consolidation of the empire with Babylon as its capital, because in the story Marduk, although one of the younger gods, is made the champion and leader of the others. The tablets on which the legend is contained now usually go by the name of enuma elish, “when above,” from the opening words. The opening lines of the story relating the creation of the gods, and the latter part telling of the creation of animals and man, we have already seen. The version of creation given here is practically the one Berosus gives of the Babylonians, which is found in Eusebius and which he quotes from Polyhistor (see Appendix A).
In the beginning was chaos, consisting of a watery mass. Only two beings existed—Apsu, the Deep, and Tiamat, the universal mother. These two represent the two formative elements from whose union the gods were created. First Lakhmu and Lakhamu were born, then Anshar and Kishar, and after a long interval the other great gods. Tiamat, after having brought forth the gods, conceived a hatred for them and created a large number of monsters to aid her in a battle against them and gave the command to her son Kingu. She bore: “giant snakes, sharp as to teeth, and merciless—with poison she filled their bodies as with blood.” Anshar sends his son Anu against Tiamat, but he is afraid to face her. After Ea also has been sent in vain, Marduk offers to take up the fight, but first demands to be recognised by the other gods as their champion. Anshar summons the great gods to a feast, informs them of all that has taken place, and calls on them to appoint Marduk as their defender. The gods do so and hail him with the following words (the translation of the Assyrian texts is based upon that of Jensen[h] in his Cosmologie der Babylonier):
Thou art the most honoured among the great gods
Thy fate has no equal, thy decree is Anu.
Marduk, thou art most honoured among the great gods
Thy fate has no equal, thy decree is Anu.
From now on thy word shall not be altered,