How did leadership in sumer change from priests to kings?

Leadership in Sumer evolved from priests to kings as societies became more complex and required centralized authority for governance and military organization. Initially, priests held power due to their roles in managing religious practices and temples, which were central to Sumerian life. However, as city-states expanded and faced external threats, the need for strong, secular leadership emerged, leading to the rise of kings who combined religious and political authority. This shift reflected a transition towards more organized governance and the emergence of state power in the region.