The Pogues in general and Shane MacGowan in particular garnered a (not entirely undeserved) reputation as a bunch of drunken paddies, and the songs sounded like that's what they were. Heck, I suspect that many of us were drawn to the band for that reason. Yet on closer inspection, the songs -- both in terms of the music and the lyrics -- are full of historical, literary, and political references not normally found in popular music, and I found that picking up the references added another level of enjoyment to the music. Songs that make you drink and think... a tough combination that the Pogues pulled off magnicifently.
Of course, it's all a bit sour for me now that I've seen If I Should Fall From Grace: The Shane MacGowan Story, in which Master Shane demonstrates himself to be a sad sot waiting around to die.
Also, I just thought I'd point out that St. Patrick was born in Scotland (Ha! Albainn gu brath!) to a Romano-British father and a (probably) Gaulish mother. His first exposure to Ireland was when he taken as a slave by Irish raiders in his teens, and it was this experience that galvanized his religious conviction.
Then there are the snakes... When it is said that Patrick drove out the snakes, it most likely refers to his work converting the Celtic people of Ireland to Christianity, thus "driving out" those dastardly druids and whatever other forms of paganism were previously enjoyed.
And really, I'm not hatin' on my Irish brethren. One love, y'all.