 One notorious captain, known as Grote Gherd ("Big Gerry"), captured 13 ships from Flanders in a single expedition.In 1648 the Prince-Archbishopric was transformed into the Duchy of Bremen, which was first ruled in personal union by the Swedish Crown.In November 1654, after the Second Bremian War, Bremen had to cede Bederkesa and the settlement of Lehe to the Duchy of Bremen (Treaty of Stade, 1654).