Most of the other Ancient Near Eastern cultures see the divine realm as quite heavily populated with gods, often having different interests and colourful personalities. The world is usually seen as coming into being through violence, either between squabbling deities or between the gods and a primeval chaos monster, whose slain body forms the stuff of the world. The relationships between human beings and gods are not generally very friendly: either human beings are created to be slaves for the gods, or they may be on good terms with some gods and not with others.
The contrast with Genesis is striking. In Genesis, God is alone, and the measured, ordered creation comes into existence by the sheer benevolent power of God. Sun, moon and stars, often seen in ancient cultures as powerful deities, requiring worship and propitiation, are merely among the things that God creates in Genesis, and God decides their proper role and sphere (1.14-19). In Genesis, God creates human beings with the deliberate intention of sharing the ordering of creation with them (1.26). Over and over again, Genesis emphasises the peaceful origins of the world, and its innate goodness. So the story of degeneration that follows does not reflect an eternal dualism in the cosmos between good and evil, and it does not suggest that there is anything more powerful than God at work.
So it reads as though Genesis is a deliberate challenge to the accepted understanding of the origins of the universe. Genesis is looking at what the culture around it believes about the nature and purpose of the material world, and disagreeing with it profoundly.