During the Battle of Thermopylae, how many Persians were killed by the 300 Spartans?
As many as 20,000 Persians were killed by the Greek forces. The actual amount that was killed by the Spartans themselves is not known, as the Greek forces did not consist just of three-hundred Spartans. The coalition actually had about 7,000 Hoplites, but did not spare any more than 300 as an advance guard, because of an upcoming festival.
