As the god of the sky and ruler of all gods, Zeus was often referred to as the supreme ruler of all. With his wisdom and power, he upheld law, justice, and morals; these qualities he possessed made him the spiritual leader of both gods and mortals.
He was also the youngest son of Cronus and Rhea, the immortal Titans who ruled the world before the era of the Greek gods. When Zeus was born, his father intended to swallow him as he did with his other siblings in order to prevent a future clash of powers between Cronus and any of his children. Instead, Rhea took Zeus and hid her newborn baby in a cave in Mt. Dicte to avoid her son from the terror of his father. As many would have predict at this point, Zeus grew up as a powerful individual and forces his father to vomit his siblings he had swallowed, and joined him into fighting for the control of the universe against Cronus and the Titans, which they eventually ended victorious at the end.
As we look at this story about his origin, we can see how highly the people of Greece are portraying Zeus as their leader. Many of his myths are focused on his leadership and decision making, and I believe that his presence have created an ideal figure of what types of characteristics a leader should possess and the types of decisions and judgments he should make.