1. The mainland Greek cities supported revolutions by the Greek cities in Asia Minor within the Persian Empire.
2. The punitive expedition against Athens failed at Marathon, so the Persians decided that the only way to put an end to continuing disturbances was to incorporate mainland Greece within their Empire and so stop disruptions to peace within the Empire.
Two leagues - one led by Athens, the other led by Sparta.
They united 180 Greek city-states into several alliances, the first led by Sparta, the next led by Athens.
The Persian-Greek wars stretched from 499-449 BCE in several phases. There were not two distinct wars.
Darius and Xerxes.
Darius the Great and Xerxes the Great.
The Persian Empire and an alliance of Greek city-states.
The Punic Wars were a contest for supremacy in the Western Mediterranean between two rising powers. The Persian War was a contest for supremacy in the Eastern Mediterranea.
The Battle of Thermopylae took place in the second of the two Persian Wars, also known more recently as the Greco-Persian Wars.
In the Persian wars which to civilizations fought in the battle of Plateau
Darius the Great and Xerxes the Great.
There were two Persian Wars, recorded by the Greek historian Herodotus. The first was in 490 BC, and the second was in 480-479 BC. If the question is about the Persian Gulf War, it was in 1990-91.
Athens emerged with an empire by keeping coontrol of the anti-Persian league and its money after peace was made. A counter to this empire was formed as the Peloponnesian League led by Sparta. The two groups ended up in a devastating 27-year Peloponnesian War.