region in eastern France, from Medieval Latin Lotharingia, literally "Lothar's Realm," name later given to the northern portion of the lands assigned by the Treaty of Verdun (843 C.E.) to Lothair I in the first division of the Carolingian empire. His empire stretched from the North Sea to the Mediterranean. Before his death (855 C.E.), Lothair subdivided his lands among his three sons. His son, Lothair (for whom the region is named), was given Lotharingia as his kingdom.