Few parts of Europe changed hands as often as Alsace and part of Lorraine. French, then German, then French again, and briefly German once more, the region left its families with records in two languages and ancestors who may have carried two nationalities in one lifetime. This guide explains the history that matters to genealogists and how to find your ancestors across the language divide.
The history in brief
France ceded most of Alsace and the Moselle part of Lorraine to the German Empire under the Treaty of Frankfurt, signed on May 10, 1871, after the Franco-Prussian War. The region returned to France after World War I, and it was occupied and effectively annexed by Germany again during World War II. A family in Strasbourg or Metz may therefore appear in French records, German records, and French records again, all within a few generations.
The départements
- Alsace: Bas-Rhin and Haut-Rhin, whose archives are now managed together as the Archives d’Alsace.
- Lorraine: Moselle, which was annexed in 1871, and Meurthe-et-Moselle, Meuse, and Vosges, which stayed French.
Note that the parts of Lorraine that stayed French and the part that became German have different records for the 1871–1918 period. Check which side of the border your ancestor’s commune fell on. See our guide to French regions for how it fits together.
The optants: a choice that scattered families
The 1871 treaty gave residents of the annexed territory a choice: stay and become German citizens, or keep French nationality and leave. Those who chose France were known as optants, and many moved to the interior of France, to Algeria, or overseas, including to the United States. Records of the optants have been digitized, and Geneanet hosts a collaborative project to index them, which makes it a useful place to search if you suspect an ancestor left Alsace-Lorraine in the early 1870s.
Records in German
Between 1871 and 1918, civil registers in the annexed territory were kept in German, by civil registry offices modeled on German practice (Standesämter). Expect German forms, German vocabulary, and often older German handwriting. Parish registers, which are separate, may be in French, Latin, or German depending on the parish and period. A short German word list, in addition to our guide to reading old French records, will take you far.
Names and places in two languages
Towns often had both a French and a German name, and the one on a document depends on the period. A record from 1895 might use the German name of a commune, and the French index of the same record the French one. Likewise, surnames carry both Germanic and French spellings, and the same person may be recorded as Schmitt, Schmidt, or in a gallicized form. Keep a list of both name forms for every commune and every surname, and search under each.
Emigration from Alsace-Lorraine
Alsace sent many emigrants to the Americas. In the 1840s, colonists from Alsace settled in Texas, where the town of Castroville was founded in 1844 with settlers from the region, and the loss of the territory in 1871 sent a further wave across the Atlantic, including many Alsatian Jews. Read more in our history of French emigration to America.
Where to search
- The Archives d’Alsace and the Moselle archives hold the registers and publish many of them online. Our archives guide explains how to use them.
- Geneanet is strong for Alsace-Lorraine trees and hosts the optants project.
- MyHeritage offers name indexes for French collections and, with its strength in Europe, can help trace families who crossed borders. See our comparison guide.
- FamilySearch has records and a FamilySearch Research Wiki on France with regional guidance.
Practical tips
- Identify both the German and the French name of the commune before you search.
- For 1871–1918, expect German-language civil registers.
- Search for variants of the surname in both languages.
- If a family disappears in the early 1870s, check the optants records.
- Remember that men may appear in German military records for the period, rather than French ones.
Illustrative composite (not a real family): A researcher in Ohio knows her great-grandfather was born in 1888 in a village in Moselle. Searching French indexes finds nothing, but the German-language civil register of the period, found through the archives site under the German name of the village, gives his birth, his parents, and their trade.
For the full method, return to our complete guide to tracing French ancestry.
Jewish ancestry in Alsace and Lorraine
Alsace and Lorraine have one of the oldest Jewish communities in France, and Jewish families appear in civil registers from 1792 like everyone else. In 1808, Napoleonic decrees required Jewish families to adopt fixed surnames and register them, which produced lists of use to genealogists. Many Jewish families left Alsace in the nineteenth century, including after 1871, for the United States and elsewhere. Alongside civil registers, community records and rabbinical sources may help.
The “malgré-nous”
During World War II, when the region was effectively annexed by Germany, young men from Alsace and Moselle were conscripted into the German army against their will. They are known as the malgré-nous, “in spite of ourselves.” If an ancestor’s twentieth-century service records seem to show a German uniform, this is often the explanation, and it affects both family history and the records you should search.
Common questions about Alsace-Lorraine research
- Is my ancestor French or German? Both, depending on the date. Nationality changed with the border, so look at the period of each record.
- The commune appears under two names. Which should I search? Search both, since a record may be indexed under either.
- Why do names vary so much? The same family may be written in French or German form, and spelling shifted with the language of the clerk.
- Where do I start if I do not know the commune? Check naturalization papers and passenger lists, as in our guide to finding the commune of origin.
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