Dominium maris baltici

The establishment of a dominium maris baltici[nb 1] ("Baltic Sea dominion") was one of the primary political aims of the Danish and Swedish kingdoms in the late medieval and early modern eras.

[1][2] Throughout the Northern Wars the Danish and Swedish navies played a secondary role, as the dominium was contested through control of key coasts by land warfare.

[3] The term, which is commonly used in historiography, was probably coined in 1563 by the King of Poland, Sigismund II Augustus, referring to the hegemonial ambitions of his Swedish adversaries in the Livonian War.

[14] To achieve this aim, Valdemar sold Danish Estonia to the Teutonic Order state in 1346, consolidating his finances and raising an army from the revenue.

[15] Atterdag's daughter and de facto successor, Lady Margaret, managed to concentrate the crowns of Denmark, Norway and Sweden in her Copenhagen-centered Kalmar Union from 1397.

[17] The Sound Dues, imposed until 1857 and constituting a primary source of income for the Royal treasury, quickly became a contentious issue, which brought Denmark into conflict with the Hanseatic League and the neighboring powers.

Sweden had sought to secure her dominium maris baltici by turning many towns (e.g. Riga, Narva, Wismar) into fortresses, often under the aegis of Erik Dahlbergh.

[23] Since the Thirty Years' War, Sweden collected customs (Licenten) from merchant vessels on the Baltic Sea, in Swedish as well as in non-Swedish ports.

[24] These customs were calculated as a certain percentage of the value of transported goods, and once payment took place in any port, the respective receipt was valid for the whole dominium maris baltici.