Lorraine is a region of France, where you find the cities of Metz and Nancy. It is located in the North-East of France, at the border with Germany. It is often associated with the Alsace region, because of the World Wars: they've been annexed to Germany (not the whole Lorraine, indeed, only the Moselle "sub-region"). There's a song whose lyrics are "Vous n'aurez pas l'Alsace et la Lorraine" (which can be roughly translated to "You won't get Alsace and Lorraine").
There are four "sub-regions" (is it an equivalent of a American county?), that are called "département" in French. These are: Meurthe et Moselle, Meuse, Moselle (those names come from river names), and Vosges.
The Lorraine region was created after Charlemagne's death, when his three sons shared its empire. One of these parts was called Lotharingie (because its king was named Lothar).
Lorraine was a French dukedom, and was once a present for Poland's king, Stanislas (in 1737).
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