What happened during the persian wars?

The Persian wars also known as "Greco-Persian wars" were fought between the Persian empire and the Greek city-states from 499 to 479 B.C. which took place in Greece and Asia Minor. Basically what happened was the expansion of the Persian Empire under the rule of Darius from the Middle east to Africa, South East Asia and Asia Minor. Next step was invading Greece.

There were two mainland invasions of Greece, in 490 (under King Darius) and 480-479 B.C. (under King Xerxes). The Persian Wars ended with the Peace of Callias of 449, but by this time, and as a result of actions taken in Persian War battles, Athens had developed her own empire. Conflict mounted between the Athenians and the allies of Sparta. This conflict would lead to the Peloponnesian War during which the Persians opened their deep pockets to the Spartans. Greece finally won the war.

because the vietnam war was fought in an especially brutal and untraditional way