Sparta first declared war on the Athenians, and for a majority of the first half, Sparta led invasions on the Greek City-State, Athens, in their territory, Attica. This battle seemingly began as the battle between that of an oligarchy and democratic systems. Unfortunately, in the midst of battle, a plague broke out in Athens and killed Pericles, their strategic leader. Eventually, the Spartans concluded their invasion of Attica, and peace was established through the Peace of Nicias.

Source: Robinson, Eric. “Thucydides and Democratic Peace.” Journal of Military Ethics, vol. 5, no. 4, 2006, pp. 243–53. Crossref, doi:10.1080/15027570601048720

Image: Map_Peloponnesian_War_431_BC-fr.svg: Marsyas.Map Peloponnesian War 431 BC-en.svg. 1 January 2011. WikiMedia Commons. https://commons.wikimedia.org/wiki/File:Map_Peloponnesian_War_431_BC-en.svg. Accessed December 9 2020.

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