I didn't know this until reading it, but a Culchie is the Irish equivalent of a hillbilly. Some of the entries are pretty funny. So if you search on Culchie, there's a lot of information about Culchies including The Culchie Dictionary of Ireland. My favorite definition: "A Thundering fuck : An unreliable person"
There's also a Culchie Festival.
It goes without saying that we Americans know very little about the world outside our borders, but we don't even know much about English-speaking white people to whom many of us are related.