"Civilization began in Sumer" refers to the idea that the earliest known civilization emerged in the region of Sumer, located in present-day Iraq, around 4000 BCE. Sumer was home to a complex society that developed many important innovations, such as the wheel, writing, and irrigation systems.
In Sumer, the relationship between kings and priests was closely intertwined. The king was seen as the representative of the gods on earth and was responsible for maintaining the divine order of the universe. The priests, on the other hand, were responsible for performing the necessary rituals and sacrifices to appease the gods and ensure their favor. The king and priests worked together to maintain social order and reinforce the religious beliefs of the society.