Question

How did the Greeks meet the threat of invasion by the Persians

Answer 1

They tried first to block the invasion in northern Greec with a land and naval force at the pass of Tempe but retired when this could be outflanked.

They then tried to destroy the Persian fleet at Artemesion opposite the strait at Thermopylai but lost.

They then organised and won the sea battle at Salamis, which removed the amphibious threat from the southern Greek cities and allowed them to send their armies to join up for a land battle.

They then concetrated their armies at Plataia and defeated the Persian army and its Greek allies.

At the same time they destroyed the remainder of the Persian fleet at Mykale.