I am attempting to research my husbands ggreat grandfather, William McConnell born. est. 1835-1840. He came to the US as a teenager. No one in the family seems to know where in Ireland he was from. I was wondering if anyone would know if I could somehow break it down in the census by only looking at the towns where the McConnell's were Roman Catholic? I seem to be getting a lot of results for the name in Northern Ireland and most of them are Presbyterian or some other religion.It would still be like looking for a needle in a haystack, but it would help a little. Thank you so much for anything you can do.