Isn't the most popular myth about 300 Spartans facing off against the powerful Persian Empire bent on conquering Greek lands? Which is based on a historical eve

Isn't the most popular myth about 300 Spartans facing off against the powerful Persian Empire bent on conquering Greek lands? Which is based on a historical event, but there were several thousand other Greeks helping the Spartan warriors in a narrow pass, because fighting in the open would have benefited the much larger Persian force.