Alsace-Lorraine was territory west of the Rhine River that was part of the Holy Roman Empire of the German Nation.. For over 700 years It was known as Elsass-Lothringen… from the 10th to the 17th century… populated with people who for the most part spoke Alemannic German dialects. However, France long desired their eastern border to extend to the Rhine and this eventually led to Alsace being conquered by Louis XIV in 1681, while Lorraine was taken in the 18th century under Louis XV.
Taking this German land was possible because the German Empire was a very decentralized government, consisting of hundreds of sovereign regions, hard to control let alone unite for a regional conflict. The final blow for this fragmented Empire came in 1806, when the entire Holy Roman Empire of the German Nation was dissolved by the French under Napoleon.
Seven years later the defeat of Napoleon in 1813, and again in 1815, led to a desire by Germans to re-unite their fractured country. They wanted a new and stronger German Nation, a second Reich, but this dream was not realized until 1871, when the strongest German state, Prussia, defeated France. The new German Empire was proclaimed to the world by Prussia’s King Wilhelm from France’s Versailles Palace. In the terms of armistice, Prussia did not forget the people of Alsace Lorraine…France was required to return Alsace-Lorraine to Germany.
Forty-eight years later, after WWI, France was again given possession of Alsace Lorraine by the Allies. But this action, along with many other unfair land grabs and huge monetary extortion inflicted by the short-sighted Allies, caused enough anger and resentment in Germany to set the stage for a second World War. Thus, only 20 years later in 1940, France was defeated and Alsace Lorraine once again was part of Germany.
After WW II, Germany lost the war and Alsace Lorraine was again given to France…even though 90% of the villages/towns/cities had German names, that the people who lived there had German names, and that those people had German customs. Right or wrong, it appears that this time the area will probably remain with France.