their independent development. [Sidenote: Frederick and Germany.] After the peace, Frederick’s main occupation lay in Germany. During the Emperor’s Italian troubles the power of Henry the Lion had gone on increasing. In the north in particular, Henry had renewed the ancient policy of extending the German race at the expense of the Slavs. Using his Saxon duchy as the basis of his operations, he completed the Germanisation of the lands between the Elbe, Baltic, and Oder, that, despite the work of the Ottos, and Lothair and Albert the Bear, were still largely Slavonic and heathen. So solid was his power, that disasters in Italy, such as in the days of the Ottos, had led to a Slavonic reaction in the north-east, had no influence in retarding the march of German conquest. Before long, the vastness of Henry’s resources and the stability of his policy threw the exploits of Albert the Bear into the shade. In alliance with the young Valdemar I. of Denmark, Henry carried to a completion the long process of the conquest of the half-heathen tribes beyond the Elbe, and grudged his reluctant ally a share in the spoils of war. The warlike Abotrites were at last subdued and forced to profess Christianity, and the fortress and bishopric of Schwerin was established by Henry in their midst, along with numerous colonies of Saxons and Flemish settlers. [Sidenote: Henry the Lion and the Marks.] Henry was as great a founder of towns as Otto the Great. Lübeck, founded in 1143 by his dependant, Count Adolf of Holstein, and the first German town on the Baltic, owed its existence to his energy. The bishoprics of Mecklenburg and Pomerania claim him as their founder. Cistercian and Premonstratensian missionaries crushed out the last remnants of heathenism, and trade followed strong rule. In 1168 Henry married Matilda, the daughter of Henry of Anjou, an alliance that established a warm and permanent connection between the Guelfic house and the English throne. [Sidenote: Henry the Lion and his duchies.]