History of Sweden (1611–1648)

During the 17th century, despite having scarcely more than 1 million inhabitants, Sweden emerged to have greater foreign influence, after winning wars against Denmark–Norway, the Holy Roman Empire, Russia, and the Commonwealth of Poland-Lithuania. Its contributions during the Thirty Years' War under Gustavus Adolphus helped determine the political, as well as the religious, balance of power in Europe.

On March 6, 1604, when Duke John, son of John III of Sweden and brother of Sigismund III Vasa, formally renounced his hereditary right to the throne, Charles IX of Sweden styled himself king. At the Riksdag of the same year, the estates committed themselves irrevocably to Protestantism by excluding Catholics from the succession to the throne, and prohibiting them from holding any office or dignity in Sweden. Henceforth, every Roman Catholic recusant was to be deprived of his estates and banished from the realm. It was in the reign of Charles IX that Sweden became not only a predominantly Protestant, but also a predominantly military monarchy. This change, which was to give a martial colouring to the whole policy of Sweden for the next hundred and twenty years, dates from a decree of the Riksdag of Linköping establishing, at the urgent suggestion of Charles, a regular army; each Province in the country being henceforth liable to provide and maintain a fixed number of infantry and cavalry for the service of the state. Their immediate enemy was Poland, now dynastically as well as territorially linked to Sweden.

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