Changes

Athens growing ambitions led to tensions with its neighbors and eventually led to a war. This conflict involved Athens and Corinth, with the latter receiving some support from Sparta. This war ended with a peace treaty and a ‘Thirty Years Peace.’ This treaty, in theory, guaranteed Athens and Sparta their respective spheres of influence. Corinth and other members of the Peloponnesian League were unhappy about Sparta’s lack of leadership. Some leading Spartans became concerned that their inaction would push the other major Greek powers, to side with Athens. During the so-called thirty Year Peace Athens grew ever stronger and in many ways arrogant, as seen in its increasing haughty attitude to its subject city-states.

====Long-term Factors in the Outbreak of War====

The underlying cause of the war was the rapid rise of the Athenians. They had grown from just another city-state into an Empire. During and after the Persian Wars, it had transformed itself and became a major trading and maritime power.<ref>Cawkwell, George. <i>[https://www.amazon.com/gp/product/B000FA5ZGY/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=B000FA5ZGY&linkCode=as2&tag=dailyh0c-20&linkId=b0d12599fc35ad97a1a071a79c90ab5e Thucydides and the Peloponnesian War]</i> (London: Routledge, 1997), p 67</ref> It had developed into the greatest maritime power in the Greek world and could dominate the trade routes in the eastern Mediterranean. It had emerged as a great Empire in a quick period, and this upset the traditional balance of power. For many decades’ Sparta, had been the greatest military power in Greece. Sparta's well-disciplined and much-feared army was the source of its military power. The Spartan Hoplite was considered the best soldiers in the Greek world.<ref>Hanson, Victor Davis. <i>[https://www.amazon.com/gp/product/0812969707/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0812969707&linkCode=as2&tag=dailyh0c-20&linkId=2988ca75b4a6858afae8101e8c5ce3d0 A War Like No Other: How the Athenians and Spartans Fought the Peloponnesian War]</i>. (New York: Random House, 2005), p. 56</ref>