Christian IV of Denmark-Norway had started the Danish-Norwegian intervention in the Thirty Years' War by invading the Holy Roman Empire in 1625. Initially successful, he suffered setbacks when his armies were defeated in the battles of Dessau Bridge and Lutter am Barenberge in 1626. In the following months, the Danish armies were forced to abandon their gains on Imperial soil and parts of Denmark herself, and retreated to the Danish isles while the Imperial army of Albrecht von Wallenstein subsequently occupied the North German plain.
The Duchy of Pomerania, which included Wolgast, capitulated to the Empire at Franzburg in November 1627. The Baltic Sea, however, remained under Danish control, due to the lack of an imperial navy. The Emperor Ferdinand II gave Wallenstein the Duchy of Mecklenburg in January, and promoted him "General of the Oceanic and Baltic Seas" in April 1628. Together with Spain, Wallenstein made plans for a Baltic imperial navy. Denmark and Sweden reacted by concluding an alliance, also in April. The Pomeranian port of Stralsund, some 70 kilometers west of Wolgast, refused to accept the Capitulation of Franzburg and with Danish and Swedish support successfully resisted Wallenstein's siege. In addition to the support for Stralsund, Christian IV had resorted to a strategy of amphibious ambushes, using his naval superiority to make landfalls on Fehmarn and in Eckernförde, and destroying the naval facilities in Ålborg, Greifswald and Wismar - all in imperial hands.