At the same time in 794, as a fresh experiment in policy, every third man was transported; while the king was assisted in his work of conquest by the Abotrites who inhabited a district east of the Elbe.
Two years later a final campaign was undertaken, when a large number of these people were transported into the country of the Franks and their land was given to the Abotrites.
He engaged in a successful expedition against the Abotrites, or Obotrites, in 1147, and won a considerable tract of land beyond the Elbe, in which were re-established the bishoprics of Mecklenburg,' Oldenburg 2 and Ratzeburg.
Adolph II., count of Holstein, was compelled to cede Lubeck to him in 1158; campaigns in 1163 and 1164 beat down further resistance of the Abotrites; and Saxon garrisons were established in the conquered lands.
Having in 842 crushed a rising in Saxony, he compelled the Abotrites to own his authority, and undertook campaigns against the Bohemians, the Moravians and other tribes, but was not very successful in freeing his shores from the ravages of Danish pirates.