Dubs call people from "down the country" Culchies. It's the Irish equivalent of "rednecks" or "hicks" or "hayseeds," I suppose. Cuchies call thems livin' in "the Big Smoke" a name right back: they call them "Jackeens," then everyone has a good laugh. I still wouldn't recommend any outsiders hearing a funny accent to pipe up, though.
There are thirty-two counties in Ireland, North and South. Each one of them has its own accent. Right off the boat, years ago, I was staying with a family down in County Cork. The ma had to translate for the father. Accents from Cork or Kerry or County Donegal can be almost impenetrable.
Dublin has (roughly speaking) a third of the nation's population, and growing. Tons of people from down the country are moving to the city. One of the nicest people I ever met was this one I worked with. She was from "Stab City," which is what they call Limerick. This other time, in a pub called The Mill down in Stillorgan, me workmates were slagging off this one from Dundalk. They were calling him a "bog hopper."
"I'm not a boghopper. From Dundalk. It's an urban area!"
"Yer a boghopper!!!"
"It's Dundalk! Where the Corrs are from!!"
"The Corrs! They're a bunch of boggers too!"
"May be- but good lookin' ones!"
"Even the bloke?"
(A guy and his three sex symbol sisters make up the pop band The Corrs.)
"Yea, specially the bloke! All us blokes from Dundalk are good lookin."
"Ah, ya culchie ya!"
"Fuck ya's!"
Informed sources have told me the term "culchie" originated in County Mayo. The people from Mayo called it to residents of this real bog warrior spot Caoilte Maith ("Good Water" in Irish). Then people outside Mayo started calling everyone from Mayo culchies. Then people--- well, you get the picture.
Anyway, the point is that just like cities anywhere, Dublin has a mix of natives and newcomers. It's an exciting mixing spot.

Guide Index Red words? Check the Dub Glossary!