Henry the Proud was confident that he would succeed Lothair, who had died on his return from Italy in December 1137; but, by a hasty and irregular election, Conrad of Hohenstaufen, duke of Franconia, was chosen king in March 1138. Henry the Proud rebelled and was declared to have forfeited his two duchies, Saxony and Bavaria, the former being given to Albert the Bear, margrave of Brandenburg, and the latter to Leopold IV., margrave of Austria. Henry defended his rights with vigour and once again Germany was ravaged by war, for although he was unpopular in Bavaria he was strongly supported by the Saxons, who, since the time of Henry IV., had always been ready to join in an attack on the monarchy, and he had little difficulty in driving Albert the Bear from the land. However, in October 1139 Henry died suddenly, but his young son, Henry the Lion, was recognized at once as duke of Saxony, while his brother, Welf, upheld the fortunes of his house in Bavaria. The struggle went on until May 1142, when peace was made at Frankfort. Saxony, with the assent of Albert the Bear, was granted by Conrad to Henry the Lion, and Bavaria was given to Henry Jasomirgott, who had just succeeded his brother Leopold as margrave of Austria. But this was only a lull in the civil strife, which was renewed after the king had made a successful expedition into Bohemia. The princes clerical and lay were fighting against each other, and the Bavarians were at war with the Hungarians, who gained a great victory in 1146. Notwithstanding the many sources of confusion Conrad was persuaded by the passionate eloquence of Bernard of Clairvaux to take part in the second crusade; he left for the East in 1147 and returned to Germany in 1149, to find Welf again in arms and Henry the Lion claiming Bavaria. The king had done nothing to stem the rising tide of disorder when he died at Bamberg in February 1152. During this reign the work of conquering and Germanizing the Slavonic tribes east of the Elbe was seriously taken in hand under the lead of Albert the Bear and Henry the Lion, and the foundation of the margraviate of Brandenburg by Albert tended to make life and property more secure in the north-east of Germany. Frederick I. becomes king.