As an Aussie, I have to say the stereotypes are as follows;
Irish: Mad, heavy drinkers, would back you up in a fight.
Scots: Mad, heavy drinkers, tight-arsed, would back you up in a fight unless you owed them 5p.
Welsh: Slightly mad, would probably stop a fight in its tracks by simply yelling out 'Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch' .
English: A bit slow, pasty, couldn't drink a nun under the table, would run from a fight even if it was their best friend.
Just a stereotype, but half of that word can be read as 'typical'