British have something very civilized, Americans(Sorry, talking stereotype here, not judging) ofter say their country is the best without ever been out of it and Germans tend to speak in a loud voice.
British people are civilized and very posh. Germans speak very harshly and loud. Australians (from what I've heard) are very relaxed and chill. French people are lovey-dovey and like cheese and champagne. Asian people are smart. I can't think of any other stereotypes...