What was a major factor in Greece's victory in the Persian wars?

Answer 1

The combined strength of the navies of the Greek city-states.

It destroyed Persian sea dominance at the battle of Salamis. This allowed the Greek cities to come from defending their cities , concentrate and defeat the Persian army the following spring.

Answer 2

Loss of the battle of Cyprus in 450 BCE finally persuaded the Persians to give up their 50-year long attempts to enforce peace on the Greek cities in the Eastern Mediterranean, and the Peace of Callias was signed the following year.

Answer 3

The Persian invasion of Greece 480-479 was repelled by victories at Salamis, Plataea and Mycale. Then battles at Eurymedon 466 BC and Cyprus 450 BCE, after which the Persians agreed to stay away from Greek city-states.

Answer 4

Establishing control of the sea, which reduced Persian capacity to go on the offensive and supply their armies. A series of sea-land battles was won by the Greeks after they attained this dominance.