Kingdom of Sweden (1523–1611)

The Early Vasa era is a period that in Swedish and Finnish history lasted between 1523–1611. It began with the reconquest of by Gustav Vasa and his men from the Danes in 1523, and Sweden's consequent abandonment of the Kalmar Union, and continued with the reign of Gustav's sons Eric XIV, John III, John's son Sigismund, and finally Gustav's youngest son Charles IX. The era was followed by a period commonly referred to as the Swedish Empire when Sweden acted as a Great European power.

Gustav's reign was marked by internal political and religious reforms, including the Protestant Reformation and a unification of the provinces. At the death of Gustav in 1560, he was succeeded by his oldest son Eric. Eric was intelligent and skilled, but was in a constant strain with his brother and other noblemen. He engaged in warfare against both Denmark, Russia and Poland, but suffered periods of insanity in 1567. In 1568 he was dethroned and succeeded by his brother John.

John stabilized the international situation and made peace. He also wanted to partially restore Roman Catholicism but the idea did not come through in the end.

At the death of John in 1592, his son Sigismund succeeded him. Sigismund was already ruler of the Polish–Lithuanian Commonwealth, through his mother, and he would rule Poland from 1587 to 1632. He set up a regency and continued to reside in Poland. On learning about the Uppsala Synod, that finally declared Sweden's Lutheran doctrines, he returned home to protest. He found that the Riksdag of the Estates had already dethroned him and replaced him by Gustav Vasa's youngest son, his uncle, Charles IX. A brief civil war ensued that Sigismund lost in 1598, where after he fled the country never to return.

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