Research Guide

Alsace-Lorraine: Was Your Ancestor French or German?

By François · Racines Genealogy · Published August 18, 2026

Some version of this message appears in every genealogy group, every week. My grandfather always said the family came from Alsace-Lorraine. I cannot find it anywhere on Ancestry. My DNA shows a little German. And anyway, didn't the border keep moving, so nobody ever really knew which country they were in?

Every part of that is worth answering, and the last part is worth correcting, because it is the belief that stops most people from searching at all.

The border did not keep moving

It moved four times in seventy-five years, on dates you can look up, and then it stopped. Between those dates, nothing was uncertain. A family living in a village in 1885 knew perfectly well which empire they belonged to, paid taxes to it, and were registered by its clerks in its language.

So the question is never was my family French or German. It is what year. Give me the year, and I will tell you the answer, the language the record is written in, and which building it sits in today.

Four dates. If your ancestor was born in 1863, the record is French. In 1885, German. In 1925, French again. There is no grey zone, and there is no reason to give up before you have started.

Alsace-Lorraine is not a place, it is a period

This is why the searches come back empty. Alsace-Lorraine was the name of a German imperial territory that existed from 1871 to 1918 and has not existed since. Typing it into a search box is like searching for a birth in Prussia or in the Confederacy: you are naming a state, not a location.

Records were never filed under it. They were filed, then as now, by commune, the French village or town, which is the smallest administrative unit and the one that has never moved. Find the commune and you have found the record. Search the territory and you will find nothing, for ever.

If the way France is stacked, from region down to commune, is not yet clear to you, it is worth ten minutes: the French pyramid explained.

Which villages were actually affected

Not all of Alsace and Lorraine changed hands, and this trips up more searches than people realise. What Germany took in 1871 was:

• the whole of the Bas-Rhin;
• the Haut-Rhin, except the arrondissement of Belfort, which stayed French and is a separate department to this day;
• most of the Moselle, the Lorraine half of the name;
• from the old department of the Meurthe, the arrondissements of Sarrebourg, minus nine communes, and Château-Salins;
• from the Vosges, the cantons of Saales and Schirmeck.

Two consequences matter for research. A family from Belfort was never German, however Alsatian it feels. And a family from a village near Nancy may have been German after all, if that village happened to fall inside the ceded arrondissements. The line followed arrondissement boundaries, not the popular idea of where Alsace ends.

What this changes in the actual document

Once you know the year, you know what you are about to open.

Before 1871 and after 1918, the act is French, on the familiar printed civil registration forms, in a French administrative hand.

Between 1871 and 1918, the act is German. Registration passed to the Standesamt, the German civil registry office, and the clerks wrote in German, in Kurrentschrift and later Sütterlin, the old Gothic cursive. This is the single biggest obstacle for American descendants, and it is a matter of practice rather than talent: the acts are formulaic, and once you know the skeleton phrases you can read them without knowing German. That is the subject of a whole guide, reading old handwriting in the records.

Given names travel with the border. The same man is Jean on his birth act, Johann on his marriage act, and John on his American naturalisation. Surnames drift too, spelled by each clerk as he heard them. If your name looks like it changed, it very likely did not: what French surnames do on the way to America.

Why the American records say Germany

This is the part that convinces families they were German all along, and it is the weakest evidence in the file.

An emigrant who left after 1871 left as a German subject. Every American document that asked where he came from, the ship manifest, the naturalisation papers, the census, the death certificate, recorded what he answered, and he answered Germany because that is what his passport said. His parents, born in the same house thirty years earlier, were French.

I have watched this happen inside a single family, on paper, in the space of eleven years. In our first published case study, an Alsatian couple declares France on their 1887 marriage return in New Jersey and Germany on their son's 1898 birth record. Nobody moved. Nobody lied. The paperwork simply caught up with 1871. You can see the document itself in From Paterson, New Jersey to Two Villages in Alsace.

The optants, the list almost nobody opens

Here is the piece of this history that is worth knowing if your family left in the 1870s.

The Treaty of Frankfurt let the inhabitants keep their French nationality on one condition: they had to declare it formally, and move out. The deadline was 1 October 1872, extended to 1 October 1873 for those already living outside Europe. Roughly 508,000 declarations were filed. About 130,000 people actually left.

Those declarations were written down, name by name, and the lists survive. They are held by the departmental archives and indexed on the genealogy platforms. If your ancestor is in them, you get his name, very often his commune, and the fact that leaving was a deliberate act rather than a vague family drift. That is a strong, dateable anchor at exactly the moment most American paper trails go quiet.

It is also a piece of family character that no census will ever give you. These people were asked, in writing, which country they wanted to belong to. A few hundred thousand of them answered.

Where to actually look

Three archive services cover the whole territory, and all three have put their registers online free of charge. You do not need an account and you do not need to pay anyone.

The method does not change with the border. Work backwards from the American records until one of them names a town, then open that town's register at the right year. Everything in this guide only tells you what you will find when you get there. Finding the town is the real work, and it has its own guide: how to find the French village your ancestor came from.

So, French or German?

Both, and neither, and it depends entirely on the year, which is why the question feels impossible until you stop asking it about the family and start asking it about a date.

People in these villages were French subjects, then German subjects, then French again, without any of them moving house. They spoke a Germanic dialect at home and signed French acts at the town hall, or the reverse, depending on the decade they were born in. The border was an event that happened to them. It was never their identity.

The village, on the other hand, never moved once. It is still there, it still has the same name, and its registers are still kept, page by page, under that name. That is what you are looking for. Not a country.

Sources. The dates and territorial detail of the 1871 cession come from the Encyclopædia Britannica entry on Alsace-Lorraine and from the text of the Treaty of Frankfurt. The figures on the option of nationality, the deadline of 1 October 1872 and the numbers who declared and who left, are those published by the Encyclopédie d'histoire numérique de l'Europe. The surviving lists of optants are held by the departmental archives; the Archives d'Alsace describe their own holding.

François is a French-born genealogist living in the United States. New to French research? Start with the complete guide to tracing your French ancestry. Going further with Alsace: finding your Alsatian ancestors, one real family, traced from New Jersey to two Alsatian villages, and the full report, with every source cited. If the family left within living memory, begin with how to find your French grandparents.