The concept of God and his historical development is an extraordinarily complex topic and it is not easily addressed in ten books. These books seek attempt to explain a complex story on how the concept of God, or single divine being, developed in different cultures, places, and across time. The history of the idea of God is long and has its roots from prehistoric to early historic periods in the ancient Near East. Later cultures developed concepts that derive from ancient Iran, Greece, Egypt, and perhaps other regions. In a period over several hundred years, in the late first millennium BC and during the first centuries AD, several faiths, including Judaism, Christianity, and Zoroastrianism emerged that took the idea of God to levels that influence us today. While no easy task, here are the ten best books that try to make sense of this complex history.