An ancestor cannot have passed down a citizenship that did not yet exist, and every country on this site has a date before which there was nothing to pass. But the cut-off dates do not all work the same way, and the difference decides real claims: an Irish line reaches back through 1922 without noticing it, and an Italian one generally stops dead above 1861.
Five dates, five verdicts. This is the citizenship by descent cut-off date read country by country, with the one thing each of them actually turns on.
Which of the five stops a line, and which does not
| Date | The state | Does a birth before it stop the line? |
|---|---|---|
| 17 March 1861 | The Kingdom of Italy | Yes. The ancestor has to have been alive on or after it |
| 18 January 1871 | The German Empire | Partly. Before it there were state citizenships, and the line is traced through those |
| 20 January 1920 | The Act defining Polish citizenship | Often. The question is whether the ancestor was ever a Polish citizen at all |
| 6 December 1922 | The Irish Free State | No. The rule turns on the island, not the state |
| 1 January 1947 | Canadian citizenship as a status | Usually not, if the ancestor was still living and connected to Canada then |
The reason the column on the right varies is that the countries wrote their rules around different things. Ireland’s turns on a place. Italy’s and Poland’s turn on a status the ancestor personally held. A place existed before the state did; a status did not.
1922: the Irish Free State, and why it does not stop anything
The Irish Free State came into being on 6 December 1922, and for a claim through a grandparent it is almost irrelevant.
Entitlement under the Irish Nationality and Citizenship Act 1956 is built on a grandparent having been born on the island of Ireland. The island is geography. A grandmother born in Galway in 1904, under a state that no longer exists, was born on the island of Ireland then and remains so now, and the line through her is open on exactly the same terms as one through a grandmother born in 1974.
So on the Irish side, nobody needs to establish that an ancestor held Irish citizenship, that they were alive at any particular moment, or that they ever set foot in the country again. What Ireland requires instead is the registration order — citizenship by entry on the Foreign Births Register dates from the registration, so a parent must be registered before a child is born for that child to inherit. The Foreign Births Register is that rule and the Irish line is the whole route. The Department of Foreign Affairs publishes the current procedure on its Foreign Births Register pages.
1920: Poland, and whether your ancestor was ever a citizen
Poland is the country where this break bites hardest, and it is the reason a Polish claim starts with a question no other country asks.
Poland regained independence in 1918, and the Act of 20 January 1920 defined who its citizens were — on the basis of domicile and connection rather than by declaring everyone of Polish descent a citizen. A great-grandfather who left Galicia in 1908 was a subject of Austria-Hungary when he sailed and was never, at any moment, a Polish citizen. There is nothing for the line to carry.
So the Polish sequence is: was the ancestor ever a Polish citizen?, then did they lose it? Both are answered from archive records rather than from a rule, and the confirmation of Polish citizenship is a finding made by a voivode on the whole file. The loss rules under the 1920 Act and the Act of 8 January 1951 that replaced it — naturalisation abroad, and under the 1920 Act foreign military service or public office abroad — are the Polish line. This is the country where a professional archive search most often changes the answer, and where it most often changes it to no.
1947: Canada, and being a British subject before it
Canadian citizenship as a status distinct from being a British subject begins on 1 January 1947.
Before that date, people born in Canada were British subjects. A person living in Canada on 1 January 1947 generally became a Canadian citizen on that day, which means a grandparent born in Ontario in 1912 who was still there in 1947 is a Canadian citizen for the purposes of a descent claim, whatever the papers say about subjects and dominions.
The harder cases are the people who had already left, or already died, before that date — and they are exactly the group the amendments of 2009 and 2015 were written to reach. The term everybody uses for them is Lost Canadians, and being inside or outside those amendments is a question of fact about the individual rather than a rule you can read off a table. The Canadian line sets out both the older breaks and the generation limit that operates independently of them, and the proof application is how a Canadian claim is actually established.
1861: Italy, and the ancestor who died before unification
Italy’s cut-off is the hardest of the five, and it is the one most often discovered late.
The Kingdom of Italy was proclaimed on 17 March 1861. Italian citizenship is a status a person held, and an ancestor who died before that date never held it — so an Italian line cannot begin above them. The working rule in every consular and judicial reading of these claims is that the Italian-born ancestor at the top of the line must have been alive on or after 17 March 1861.
There is a second Italian cut-off stacked on top of it now, and it operates on the other end of the chain: since a decree-law of 28 March 2025, converted with amendments in May 2025, recognition for a person born abroad who holds another citizenship generally requires an Italian-born parent or grandparent. So the window for an Italian claim is narrower at both ends than it was, and a great-grandparent line that cleared 1861 comfortably may now fail the generation rule. An Italian-born great-grandparent is where that lands, and the Italian line is the route as it now stands.
1871: Germany, and the state citizenship that came first
Germany’s is the cut-off that is least likely to end a claim and most likely to complicate the paperwork.
The German Empire was founded on 18 January 1871. Before that, what an ancestor held was the citizenship of a particular state — Prussian, Bavarian, Württemberger, Saxon — and German nationality law traces through those rather than treating them as nothing. The modern statute, the Reichs- und Staatsangehörigkeitsgesetz of 22 July 1913, sits on top of that history.
The German break that actually ends lines from this era is not the founding date at all. It is the rule, in force before the 1913 Act, under which a German who lived abroad for ten years without registering with a consulate lost citizenship. An ancestor who emigrated in 1885 and never went near a consulate may have ceased to be German around 1895, long before anybody in the family thought about it. The German line sets out the loss rules at each link, including that one.
1949 and 1983: the British dates that decide which rule reads your case
Britain’s dates are not about the state existing — it plainly did — but they behave the same way, because they decide which statute your case is read under.
- 1 January 1949. The British Nationality Act 1948 came into force, creating citizenship of the United Kingdom and Colonies and ending the rule that a married woman’s status followed her husband’s. Lost by marriage.
- 1 January 1983. The British Nationality Act 1981 came into force, creating British citizenship as it exists now and, going forward, allowing descent through the mother. Registration under section 4C of that Act is the route for people born before it who were excluded by the old maternal rule — the grandmother's line.
Either way the British generation rule usually decides the outcome first: a British citizen by descent generally cannot pass citizenship to a child also born outside the UK. The British line.
How to check a cut-off in one hour
You need one fact and one comparison, and the fact is on a document most families already have.
- Find the ancestor’s date and place of birth, as the place was named on the day. Not the modern country — the town, and the state that governed it then. A birth in Lemberg in 1897 and a birth in Lviv in 1997 are not the same country’s problem.
- Compare that date against the row in the table at the top of this post. If the birth is after the date, this break is not yours. If it is before, read the country’s paragraph: Ireland and Canada will usually still hold, Germany will need the chain traced through a state citizenship, and Italy and Poland are where a line most often genuinely ends.
- If the answer is that the ancestor was never a citizen, stop here. There is no application, no supporting document and no professional that turns a subject of Austria-Hungary into a Polish citizen retrospectively.
And if the birth clears the cut-off, the cut-off was never the question. Go back to the seven breaks, because the thing that stopped the line is one of the other six — most often a naturalisation before the next birth, which is the break that decides most claims.