The Imperial Territory of Alsace-Lorraine ( or Elsass-Lothringen) was a territory created by the German Empire in 1871 after it annexed most of Alsace and the Moselle department of Lorraine following its victory in the Franco-Prussian War. The Alsatian part lay in the Rhine Valley on the west bank of the Rhine River and east of the Vosges Mountains. The Lorraine section was in the upper Moselle valley to the north of the Vosges.