We likely owe our form of representative democracy to the 300. If they hadn't delayed the Persians at Thermopalae, subsequent Persian conquest would have ended the Greek experiment in democracy and there was no place else in western society from which democratic values would have likely arisen. It also led to the beginnings of nationalism. Because of the sacrifice of the 300, the various Greek city-states began to think of themselves more as Greeks than as Athenians, Spartans, etc. The History Channel is currently running a two hour Documentary on the 300 using similar visual treatment to what I believe is in the movie. It's excellent. If you have any interest in history, you may want to check it out.