The Duchy of Saxe-Wittenberg () was a medieval duchy of the Holy Roman Empire centered at Wittenberg, which emerged after the dissolution of the stem duchy of Saxony. The Ascanian dukes prevailed in obtaining the Saxon electoral dignity until their duchy was finally elevated to the Electorate of Saxony by the Golden Bull of 1356. History Ascanian struggle for Saxony The Eastphalian count Otto of Ballenstedt (d. 1123), ancestor of the House of Ascania, had married Eilika, a daughter of Duke Magnus of Saxony from the House of Billung. As the Billung male line became extinct upon Magnus's death in 1106, Otto hoped to succeed him, however King Henry V of Germany enfeoffed Count Lothair of Supplinburg. During the following long-term dispute between Henry and Lothair, Otto was able to gain the title of a Saxon (anti-)duke, though only for a short time in 1122. Lothair was elected King of the Romans in 1125 and in 1134 he vested Otto's son Albert the Bear with the Saxon Northern March. Upon his death in 1137, Albert once again strived for the Saxon duchy, which however fell to Lothair's son-in-law Henry the Proud from the Bavarian House of Welf. Albert concluded a deal with the rising House of Hohenstaufen: He backed the succession of Conrad of Hohenstaufen as German king, who in turn deprived his Welf rival Henry the Proud of the Saxonian Duchy in 1138 and gave it to Albert. However, his rule was strongly contested by the local nobility and in 1142 Albert finally had to resign as duke in favour of Henry the Proud's son Henry the Lion. Albert later took part in the Wendish Crusade of 1147 and in 1157 established the Margraviate of Brandenburg. He died in 1170. The third chance for the Ascanians came, when in 1180 ambitious Henry the Lion was deposed as Saxon Duke by Emperor Frederick Barbarossa. Frederick partitioned Saxony among his allies into more than a dozen immediate territories. Among the supporters, Archbishop Philip of Cologne received the largest share as the newly created Duchy of Westphalia. The Saxon ducal title at least passed to late Albert's youngest son, Count Bernhard of Ballenstedt, who nevertheless only ruled over small, mostly Eastphalian fringes of the old duchy. Anhalt, Wittenberg and Lauenburg Duke Bernard died in 1212 and his two surviving sons divided the Saxon heritage: the elder Henry took the old Ascanian allodial