Political unions involving Sweden

Sweden has for political and dynastic reasons been in union with other kingdoms and princely states, ostensibly personal unions.

In 1319 the infant Magnus Henriksson was crowned as king of both Sweden and Norway. In 1332 when the King of Denmark Christopher II died as a "king without a country" after he had pawned Denmark piece by piece, King Magnus took advantage of his neighbour's distress, redeeming the pawn for the eastern Danish provinces for a huge amount of silver, and thus also became king of Skåneland. The union of these three countries lasted until 1343 when Magnus preemptively let his son Haakon, succeed him to the Norwegian throne, though he would still rule as regent during his son's minority, which ended in 1355, when Haakon came of age. In 1360 the Danish king Valdemar Atterdag reconquered Skåneland.

In 1397 the three Scandinavian kingdoms of Sweden, Norway and Denmark were united in the Kalmar Union, a personal union agreed upon in the Swedish city of Kalmar. After only a few decades the relationship between Sweden and the leading power Denmark had deteriorated into open conflict. The period until the dissolution in 1521 was marked by the constant strife between Sweden and Denmark. The union was sometimes made defunct by Sweden electing a monarch separate from the union king, and on one occasion Sweden and Norway were even de facto united in a personal union in opposition to the union monarch.

In 1592 Sigismund succeeded his father John III of Sweden to the Swedish throne, but after the Polish election in 1587 and confirmation of GDL Natural and legal rights in 1588 he had also been elected king of Poland-Lithuania making him the monarch of both nations. Sigismund, who was a Roman Catholic failed however to gain support in Lutheran Sweden, and was eventually deposed and succeeded by his uncle Charles IX in Sweden 1599.

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