My grandparents were traditional Irish-Catholics. My father, his sister and my cousins all attended Catholic schools and the community did exist.

I'm not Catholic, did not go to a Catholic school and was never christened into the faith.

As far as I could tell, they were never self segregated or very insular. They just blended into the wider community.

I mean up until the 50s or 60s, maybe longer, Particularly in Liverpool, there was still a lot of Catholic/Protestant rivalry going on and people getting beaten over it but I don't know how bad it was and seems to have calmed down a lot now. Nobody gives too much of a shit about it any more to kick up a stink.