Lwów Oath

The Lwów Oath (Polish: Śluby lwowskie) was an oath made on April 1, 1656 by Polish king John II Casimir in Latin cathedral in the city of Lwów (today Lviv, western Ukraine).

During "the Deluge", when the Swedish armies invaded Polish–Lithuanian Commonwealth, which was already struggling with Muscovy, the Voivode of Poznań, Krzysztof Opaliński, surrendered Greater Poland to Swedish king Charles Gustav. Other areas also surrendered in rapid succession. Almost the whole country followed suit, with the Swedes entering Warsaw unopposed in August 1655 and John Casimir fleeing to Silesia, where he took refuge in the town of Oberglogau (Polish: Głogówek) staying there in a local castle from October 17, 1655 until December 18 of the same year.

However several places still resisted, most remarkably (and symbolically) the monastery at Jasna Góra (November 1655 to January 1656). The defense of Jasna Góra galvanized Polish resistance against the Swedes, as aggression on that place, perceived by Catholic Poles as the most holy sanctuary, rose massive anti-Swedish sentiments. In December 1655 the Tyszowce Confederation formed in support of the exiled John Casimir.

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