Irish Citizenship Through Your Great-Grandparent

Your Irish-born great-grandparent's own naturalization abroad is not a chain-breaker, whenever it happened. Section 21 of the 1935 Act ended the Irish citizenship of an adult who voluntarily acquired another nationality, and Section 5(1) of the 1956 Act repealed that rule from July 17, 1956 without retroactive effect — but Section 6(1) of the 1956 Act independently covers birth in Ireland, with no exclusion for anyone who had previously lost citizenship. As enacted it read "every person born in Ireland is an Irish citizen from birth"; since 1 January 2005 it reads that every person born in the island of Ireland is entitled to be an Irish citizen. An Irish-born ancestor who died a naturalized American is therefore a person who "would if alive have been an Irish citizen" under Section 7(1), and transmits accordingly — Section 7(2) adds that the ancestor's not having done an act reserved to Irish citizens does not by itself exclude the next generation.

Where the rule can still bite in a great-grandparent claim is one generation down: the intermediate ancestor you rely on — your grandparent or parent — was not born in Ireland, and held Irish citizenship by descent or by Foreign Births Register registration rather than by birth. Section 6(1) does not reach them, so if that person voluntarily took another citizenship between 1935 and July 17, 1956 while aged 21 or over, the date matters and the naturalization record needs to be produced.

Even then, Section 24 of the 1956 Act provides that no person is deemed ever to have lost Irish citizenship under Section 21 of the 1935 Act "merely by operation of the law of another country whereby citizenship of that country is conferred on that person without any voluntary act on his part." If the foreign citizenship arose automatically under that country's law rather than by their own application, this carve-out may apply. None of this is a finding of ineligibility — it is a question for the Foreign Births Register Unit at fbr@dfa.ie, which decides.

If your grandparent or parent did not register on the FBR before you were born, citizenship by descent is not available. The fallback is Section 16 of the Irish Nationality and Citizenship Act 1956, which allows the Minister for Justice to waive the ordinary conditions for a person of 'Irish descent or Irish associations.' It is granted at the Minister's absolute discretion and is rarely granted, but it is the provision written for exactly this situation — a documented Irish line with a broken registration chain.

The other route is ordinary naturalization under Section 15 of the same Act, which is also discretionary but additionally requires residence in the State: one year's continuous residence immediately before the application, plus four years' total residence in the eight years before that — five years inside a nine-year window. A separate provision, Section 15A, sets a shorter route for spouses and civil partners of Irish citizens: one year continuous plus two years in the preceding four, with the marriage or civil partnership subsisting for at least three years. Both are a different and much more demanding process than FBR registration, and neither can be done from abroad the way an FBR application can.