No. They are not religious – in a religious sense. They are between Catholic and Protestant but most of them don’t even attend Church – it is simply a social and political demographic. In some ways it goes back to Henry the Eighth.

So how does that tie in to IRA soldiers killing “black and tans”? Or are those two completely different conflicts?

No, not really. It’s more a power struggle and who represents who. There are also social components involved.

As much as the comments rock I still don’t completely get it. Can someone explain it in bob the builder terms?

The black and tans were recruited from prisons and the docks of the court room to go into Ireland and restore control. Needless to say they did some horrific things on patrol, including sexual assualt, criminal damage and grevious bodily harm.
I doubt that the IRA were innocent however, but I believe at this time the IRA’s violence was directed away from innocent civilians.

I would think it was originally inspired by poverty, in which the few (land-owners from abroad) were rich and well fed, while the rest (catholics) starved.. look at ‘irish famine’.

@Butlersloss is there any proof or evidence that the black and tans were recruited from prisons? Can you provide a link?

It was both – when Cromwell invaded Ireland (a Catholic country) he brought with him Protestantism and imposed a Protestant class above the Catholics. So the conflict was both a religious one and a nationalistic one. This is why the IRAs were confused politically; they were a broad-church (pardon the pun) who united against the overlords but had very diverse beliefs. This is similar to the ANC in South Africa. Hope this helps.

@whiteroseman good, unbi-est answer. Welcome to fluther.