Ireland is an unusual case because we grant citizenship based on your connection to the island rather than the country, ie pretty much anyone entitled to Britis

Ireland is an unusual case because we grant citizenship based on your connection to the island rather than the country, ie pretty much anyone entitled to British citizenship on the basis of being from Northern Ireland is also entitled to an Irish citizenship. Specifically you can be entitled to citizenship from birth if either of the following conditions are met: - at least one parent is an Irish citizen or entitled to be one and was born on the island of Ireland - you are born anywhere on the island of Ireland (including Northern Ireland) and at least one parent is an Irish or British citizen, a permanent resident of Ireland or Northern Ireland, or has been domiciled on the island of Ireland for 3 of the past 4 years You're no longer automatically entitled to Irish citizenship via a grandparent born in Ireland if your Irish parent was born overseas unless the parent's birth was registered with an Irish diplomatic mission.