Metz is a French municipality in the Moselle department, in Lorraine. It is the prefecture of the department.  Metz and its surroundings were part of the Trois-Evêchés (Three Bishoprics) from 1552 to 1790, which were enclosed between the Ducal Lorraine and the Duchy of Bar until 1766 and the Duchy of Luxembourg (until 1659).

A trading city of the Carolingian Empire, Metz was the seat of a powerful bishopric, and an important trading and banking city of the Holy Roman Empire. After the First World War, Metz became French again, but was annexed by the Third Reich from 1940 to 1944.

Known since pre-Roman antiquity, then as Mettis, it became the capital of the Frankish kingdom of Austrasia in the sixth century AD.  It was coveted by its neighbours, who were its debtors, and then by the kingdom of France. Metz became a French protectorate and stronghold in the 16th century, before being annexed by the German Empire at the end of the 19th century (Alsace-Moselle).