Polish-Swedish War (1620–1622)

Template:Campaignbox Polish–Swedish War (1621–1626) The Polish–Swedish War (1621–26) was another war in the series of conflicts between the Polish–Lithuanian Commonwealth and the Swedish Empire (see Polish–Swedish wars). It began with a Swedish invasion of Polish-Lithuanian fief of Livonia. Swedish forces succeeded in taking the city of Riga after a siege. The Commonwealth, occupied by a serious war with Ottoman Empire (battles of Cecora and Chocim) was unable to send significant forces to stop Gustav Adolf, and was forced to sign a truce favorable to Sweden. The Commonwealth was forced to cede Livonia north of the Dvina (Düna) river, and retained only a nominal control over Riga. A new truce in Mitau (Jelgava, Mitawa) was signed and lasted from November 1622 to March 1625.

The Polish–Swedish War (1617–18) showed that the Swedish Army, despite several reforms, was still unable to defeat the Polish–Lithuanian Commonwealth, despite the fact that Poland - Lithuania at the time, was involved in other conflicts, and had sent inadequate forces to Livonia. Furthermore, King Gustav Adolf was still regarded in Europe as a usurper. To safeguard Swedish crown for himself, Gustav Adolf decided to force Zygmunt III Waza to relinquish it. With help from Axel Oxenstierna, the Swedish king introduced a widespread program of military and social reforms, which resulted in creation of a highly trained army, based on native Swedish recruits.

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