Treaty of Stuhmsdorf

The Treaty of Stuhmsdorf (Swedish: Stilleståndet i Stuhmsdorf) or Sztumska Wieś (Polish: Rozejm w Sztumskiej Wsi) was a treaty signed on 12 September 1635 between the Polish–Lithuanian Commonwealth and Sweden in the village of Stuhmsdorf, Royal Prussia (now Sztumska Wieś, Poland), just south of Stuhm (Sztum).

The treaty introduced a truce for 26 and a half years. Sweden, weakened by its involvement in the Thirty Years' War, agreed to the terms that were mostly favourable to the Commonwealth in terms of territorial concessions. The king of Poland regained many of the territories he had lost in the past decades of the Polish–Swedish War, but the treaty was also beneficial to Sweden and her allies (France, England and the Dutch Republic), which wanted Sweden to be able to concentrate on the Thirty Years' War in the Holy Roman Empire, without the need to worry about possible conflict with the Commonwealth.

The truce lasted until 1655, when Sweden invaded the Polish-Lithuanian Commonwealth in the Second Northern War.

The Polish side was not unified. King Władysław IV Vasa of Poland, from the Swedish House of Vasa, wanted to regain the Swedish crown, which had been held and then lost by his father Sigismund III. As this was a daunting task, his less ambitious motivations were to gain fame and strengthen his position in the Commonwealth, where Golden Liberties made the king's position among the weakest in Europe. He hoped these goals would be achievable during the war and argued that the commonwealth could gain more by warring with Sweden; however, he was also not averse to peaceful resolution if it were to give him what he wanted. He thought the negotiations gave him the opportunity to trade his right to the Swedish crown for a hereditary claim to one of the regained lands (he was supported by the primate of Poland, Jan Wężyk), and entrusted this matter to the Prussian mediators.

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