The Greek Wars refer to a series of conflicts in ancient Greece, primarily involving the city-states of Athens and Sparta. One of the most notable conflicts was the Peloponnesian War, which lasted from 431 to 404 BCE. This war was marked by battles, shifting alliances, and significant political changes, ultimately leading to the decline of Athenian power. Another important conflict was the Greco-Persian Wars, where Greek city-states united against the invading Persian Empire. Key battles, such as the Battle of Marathon and the Battle of Thermopylae, showcased the bravery of the Greeks and their ability to overcome a larger enemy. These wars played a crucial role in shaping Greek identity and history.