To honor the ones who lost their lives during the battle (hope this helped!)
I do believe it is the Senate.
George Washington did not want to accept the presidency that the people wanted to give him for fear of becoming a tyrant himself, just like King George II of England, from whom they just declared themselves independent from. When he became president, he made an example by only taking 2 terms and then refusing to continue being president. It wasn't until much later that a law was introduced to prevent any single president from serving more than 2 terms.
The answer would be the geography of the country. Its mountain terrain and bodies of water created a boundary to each city-state. Each city-state created their own society. For example, Sparta had created a military society while Athens is the center of many intelligent people. Each city-state also has their worshipped specific gods, Aside from Zeus, Poseidon, and Hades.