Answer: Spartan soldiers and the Athenian navy fought off the Persian Empire.
Step-by-step explanation:
When the Persians invaded Greece under Xerxes to exert revenge for an earlier failed invasion, the Spartans commanded one of the best land forces in the region and the Athenians commanded a very efficient navy.
These two combined to devastating effect on the Persians with the Spartan army doing well in the Battle of Plataea and the Athenian navy scoring a decisive victory against the Persians in Salamis.