Under Adaldag the metropolitan see obtained its first suffragans, by the erection of the bishoprics of Ribe, Schleswig, and Århus; and that of the Slavic territories of Aldenburg (today's Oldenburg in Holstein) was also placed under Hamburg.
During Adaldag's leadership, the metropolitan see gained its initial supporting bishops through the creation of new bishoprics in Ribe, Schleswig, and Århus; and the Slavic territories of Aldenburg were also brought under the authority of Hamburg.