The North Side gang in Chicago wasn't really Irish, it was more a mixed group; only the first boss, Dean O'Banion, was Irish. Even George ''Bugs'' Moran wasn't Irish, but ethnic French, his real name was Adelard Cunin.
The Touhy brothers in Chicago headed a mostly Irish organization though, I think.
Willie Marfeo to Henry Tameleo:
1) "You people want a loaf of bread and you throw the crumbs back. Well, fuck you. I ain't closing down."
2) "Get out of here, old man. Go tell Raymond to go shit in his hat. We're not giving you anything."