Creation of the union
The Hanseatic League, commercial and defensive confederation of merchant guilds and their market towns, dominated the economic affairs of the Baltic. The Danish king Valdemar IV tried to break away from the league, but saw that he could not, so he tried to create a new alliance with Norway. He married his daughter Margaret with the Norwegian prince Haakon, later king Haakon VI. In 1370 they had a son, Prince Olaf, who after the death of Valdemar IV in 1376 became king of Denmark as Olaf II with his mother as regent. In 1380 king Haakon VI died, making his son Olaf king of Norway as Olaf IV. In 1387 the young king died, leaving the two countries under the rule of his mother. Meanwhile Sweden had a problem. The king Albert became very unpopular, so the nobles decided to ask for help from Queen Margaret I. In the battle of Vastergotland in 1389, Margaret’s forces together with the nobles defeated the army of Albert and captured him. Margaret took over the crown of Sweden.
To secure succession, she proclaimed her sister’s grandson Erik of Pomerania as king of Norway in 1389. Erik was around 9 years old at the time, so Margaret continued to rule as a regent. In 1396 homage was rendered to him in Denmark and Sweden. A congress of the three councils of state, the Rigsraads, was summoned in Kalmar in June 1397. On 17 June the same year, on Trinity Sunday Erik was pronounced King of Denmark, Sweden and Norway. Although Margaret was not a regent anymore, she remained in power until her death in 1412.
Erik of Pomerania and Christopher of Bavaria
After the death of Margaret, Erik could finally be a solo ruler. He inherited the distaste for the Hanseatic League. A conflict broke out with the dukes of Holstein, centered on the power over the Danish duchy of Schleswig, who joined the Hanseatic League. This ended in catastrophe for Erik, leading to an economic crisis and forcing him to leave most of Schleswig to Holstein in 1432. Erik raised the taxes in Sweden and Norway, which led to a peasant rebellion in Sweden in 1434 and soon it gained support from the Swedish aristocracy. In 1436 a similar uprising took place in Norway and latter in Denmark, which culminated in Erik being deposed as a king in 1439.
His nephew Christopher of Bavaria managed to become king of all three kingdoms in the period from 1440 to 1442. In his period the councils in each kingdom became more powerful. This marked the end of the centralized government of the kingdoms that Margaret established. Christopher died in 1448.
The battles for Sweden
Christopher left no heir, so Sweden elected Karl Knutsson as king, while Denmark chose Christian of Oldenburg as king. Christian I became king of Norway in 1450 and in 1457 became king of Sweden. In 1464 he was deposed from Sweden and Karl Knutsson returned. After the death of Karl in 1470, Christian I tried to claim the Swedish crown, but suffered a terrible defeat at the Battle of Brunkeberg in 1471. After Christian’s death in 1481, negotiations began regarding the terms of the kingship of his son Hans and of the three kingdoms. The negotiations ended, but Sweden bailed in the last moment. Hans became king of only Denmark and Norway in 1483. In 1497 a dispute broke out between the Swedish aristocracies. Hans used this and became king of Sweden too until 1501 when he was deposed.
End of the Kalmar Union
In 1513 Hans died and was succeeded by his son Christian II, king of Denmark and Norway. He continued the policy of reclaiming Sweden. Once again internal disagreements broke out in Sweden. Christian II used this and in 1520 he took over Stockholm. After his crowning ceremony, the Stockholm Bloodbath was carried out, where 82 prominent people, enemy of Christian II and opposition on the Kalmar Union, were killed. He thought that this would end all the resistance against him, but rebellion started led by Gustav Vasa. In 1523 Gustav Vasa became king of Sweden, stablishing the House of Vasa. Christian II was replaced by his uncle Frederik I as king of Denmark and Norway the same year. This marked the end of the Kalmar Union.