# The Treaty of Frankfurt cedes Alsace-Lorraine to the German Empire

Date: 1871

## The fact

On 10 May 1871 the Treaty of Frankfurt ended the war: France ceded Alsace and part of Lorraine, paid a five-billion-franc indemnity, and accepted German occupation until payment. [Bismarck](/people/otto-von-bismarck), after generals’ pressure for a military frontier, made the cession a peace condition. Option clauses allowed some inhabitants to keep French nationality by emigrating. This is the annexation statute, not Sedan. Later museums, competitions, UNESCO lists, and translations are not this Fact. The Reichstag, Wilhelm I, Moltke, Roon, and state administrations may share the file; they do not erase a documented decision, and they are not a licence to treat every regiment’s act as his handwriting.

## Context

Thiers’s government signed under occupation. Local protests in Strasbourg and Metz were not a referendum. The Reichsland was run from Berlin, not as a co-equal federal state. 1919 reversal is later and is not converted into a lifetime Bismarck Fact. Sharing demand with Moltke is required. Later museums, competitions, UNESCO lists, and translations are not this Fact. The Reichstag, Wilhelm I, Moltke, Roon, and state administrations may share the file; they do not erase a documented decision, and they are not a licence to treat every regiment’s act as his handwriting.

Shared responsibility is part of The Treaty of Frankfurt cedes Alsace-Lorraine to the German Empire. Naming Otto von Bismarck does not delete co-authors, institutions, or later transmitters. The lag from 1871-05-10 to any measured indicator is not treated as zero. Alternative explanations — weather, other armies, later statutes, or independent cultural change — remain live where the sources do not close them.

## Evidence and sources

Avalon publishes peace-instrument texts. Britannica independently dates Frankfurt and the cession. French diplomatic collections independently record the option. No Factrail original emigrant census is supplied. Later museums, competitions, UNESCO lists, and translations are not this Fact. The Reichstag, Wilhelm I, Moltke, Roon, and state administrations may share the file; they do not erase a documented decision, and they are not a licence to treat every regiment’s act as his handwriting.

Official or archival record: Avalon — Franco-Prussian peace instruments / Frankfurt terms carrier (https://avalon.law.yale.edu/19th_century/franpru.asp; Yale Avalon Project).

## Significance

Worsening displacement-and-minority path of high weight. Complex. High confidence on the treaty. Later museums, competitions, UNESCO lists, and translations are not this Fact. The Reichstag, Wilhelm I, Moltke, Roon, and state administrations may share the file; they do not erase a documented decision, and they are not a licence to treat every regiment’s act as his handwriting.

## What is established and what is not

Established: Frankfurt on 10 May 1871 ceded Alsace-Lorraine under Bismarck’s peace terms. Not established: a unique option-emigrant total, or that every Alsatian was German-speaking by consent. Later museums, competitions, UNESCO lists, and translations are not this Fact. The Reichstag, Wilhelm I, Moltke, Roon, and state administrations may share the file; they do not erase a documented decision, and they are not a licence to treat every regiment’s act as his handwriting.

Later competitions, monuments, translations, UNESCO listings, museums, and adaptations are not converted into extra lifetime acts.

If a number is not in the two records named above, it is not supplied here.

Confidence is stated on the impact path, not hidden in adjectives. Do not twin Frankfurt with the war itself or with later 1919 reversal. Mixed effects of The Treaty of Frankfurt cedes Alsace-Lorraine to the German Empire are separate paths.

The attached driver is [forced-displacement-scale](/drivers/forced-displacement-scale). The welfare reading used in this dossier is worsening. That reading is an impact-path choice, not a property stored on the Fact itself.

## People

- Otto von Bismarck: https://factrail.ai/people/otto-von-bismarck

## Drivers

- Forced-Displacement Scale: https://factrail.ai/drivers/forced-displacement-scale

## Sources

- https://www.britannica.com/event/Treaty-of-Frankfurt
- https://avalon.law.yale.edu/19th_century/franpru.asp

## Methodology

https://factrail.ai/methodology

Canonical: https://factrail.ai/facts/de-bismarck-frankfurt-alsace-1871