From the Wikipedia page 
Moselle (French pronunciation: [mɔzɛl]) is the most populous department in Lorraine, in the east of France, and is named after the river Moselle, a tributary of the Rhine, which flows through the western part of the department. Inhabitants of the department are known as Mosellans.
Moselle is one of the original 83 departments created during the French Revolution on March 4, 1790. It was created from the former province of Lorraine.
Moselle is part of the current region of Grand Est and is surrounded by the French departments of Meurthe-et-Moselle and Bas-Rhin, as well as the Germany states of Saarland and Rhineland-Palatinate and Luxembourg in the north.