The second half of Christian IV’s reign became a time of recession. The economic crisis became more severe, and at the same time the fortunes of war turned. Denmark’s participation in the Thirty Year’s War from 1625 was meant to establish the position of Christian IV as a great North European prince. Instead, he suffered a humiliating defeat to the German Emperor’s army in 1626 at Lutter am Barenberge.

From then on Sweden gradually took over as the dominant power in the Nordic region. The new balance of power became clear when another war with Sweden was fought from 1643 to 1645. At the conclusion of peace Denmark had to give up Gotland, Oesel and parts of Norway. Christian died three years later and was succeeded by Frederik III.

During the time between the two wars there was still a lot of building activity: Nyboder, the Round Tower and Rosenborg were finished during this period. In 1634 the wedding of Christian, the Prince Elect, to Magdalena Sibylla was celebrated. The wedding, known as The Great Bilager, was an enormous event meant to demonstrate that the Danish Court, in spite of the lack of the fortunes of war, still was second to none.