LOTHAIR (825-869), king of the district called after him Lotharingia, or Lorraine, was the second son of the emperor Lothair I. On his father's death in 855, he received for his kingdom a district lying west of the Rhine, between the North Sea and the Jura mountains, which was called Regnum Lotharii and early in the loth century became known as Lotharingia or Lorraine. On the death of his brother Charles in 863 he added some lands south of the Jura to this inheritance. The reign was chiefly occupied by efforts on the part of Lothair to obtain a divorce from his wife Teutberga, a sister of Hucbert, abbot of St. Maurice (d. 864) ; and his relations with his uncles, Charles the Bald and Louis the German, were influenced by his desire to obtain their support to this plan. Louis favoured the divorce, and Charles opposed it, while neither lost sight of the fact that Lothair was without male issue. Lothair put away Teutberga ; but Hucbert took up arms on her behalf, and after she had submitted successfully to the ordeal of water, Lothair was compelled to restore her in 858. He then won the support of his brother, the emperor Louis II., by a cession of lands, and obtained the consent of the local clergy to the divorce and to his marriage with Waldrada, which was cele brated in 862. A synod of Frankish bishops confirmed this decision
at Metz (863), but Teutberga fled to the court of Charles the Bald, and Pope Nicholas I. declared against the decision of the synod. An attack on Rome by the emperor failed, and in 865 Lothair again took back his wife. Teutberga, however, now expressed her desire for a divorce, and Lothair went to Italy to obtain the assent of the new pope Adrian II. On the return journey he died at Piacenza on Aug. 8, 869. He left, by Waldrada, a son Hugo who was declared illegitimate, and his kingdom was divided between Charles the Bald and Louis the German.
See Hincmar, "Opusculum de divortio Lotharii regis et Tetbergae regime," in Cursus completus patrologiae, tome cxxv., edited by J. P. Migne (Paris, 1857-79) ; M. Sdralek, Hinkmars von Rheims Kanonistisches Gutachten fiber die Ehescheidung des Konigs Lothar II. (Freiburg, 1880 ; E. Diimmler, Geschichte des ostfrdnkischen Reiches (Leipzig, 1887-88) ; and E. Miihlbacher, Die Regenten des Kaiserreichs unter den Karolingern (Innsbruck, 1881).