Clare---It's not true that no baptismal records exist before 1815 in Ireland. It all depends on the county and parish where you gg-grandfather was baptised. I have seen some baptismal records in Ireland going back into the later 1700s, but that is probably the exception rather than the rule. You need to do some searching for your gg-grandfather in the place where he lived after emigrating from Ireland, and try to pin down at least the county he was from, and proceed from there. Can you give us any dates and last names and places of residence? Good luck in your search, Mary Kay