In our (USA) history, the first Irish immigrants where Protestants. They would call themselves Scottish to separate them from the later Irish immigrants who where Catholics. Not so much religion, but more pro or anti Crown.
This may be the gayest thread yet. Men in skirts=gay.
Go to Scotland or Ireland with your American accent and tell them all about your "ancestry". You'll get laughed out of the pub. Great people and very friendly, and I had a great time in their pubs, but they told me there's nothing more ridiculous than some American thinking they're Irish...
And don't feed me that "I'm proud of my heritage" crap either.