regarded as "twin treaties", "supplementary treaties" or one treaty, which is sometimes referred to as "Treaty of Wehlau and Bromberg" or "Treaty of Wehlau-Bromberg." Ratification The preliminary treaty of Wehlau had been signed on 19 September 1657 by Frederick William I's envoys von Schwerin and von Somnitz, as well as by Warmian (Ermland) prince-bishop and Wincenty Korwin Gosiewski for the Polish–Lithuanian Commonwealth, and Habsburg delegate and mediator Freiherr . The amended and final version of the treaty was ratified on 6 November by Frederick William I and John II Casimir in Bromberg (Bydgoszcz). The Brandenburgian elector and the Polish king attended the ceremony with their wives, Luise Henriette of Nassau and Marie Louise Gonzaga, respectively. Danzig (Gdansk) Mayor Adrian von der Linde was also present. The Treaties of Wehlau and Bromberg were confirmed by the parties and internationally recognized at the Peace of Oliva, which ended the Second Northern War in 1660, and by the Polish Sejm in 1659 and 1661. Agreements The treaty ratified in Bromberg had three parts. The first one contained 22 articles and dealt primarily with the status and succession of Prussia, the Brandenburg-Polish alliance, and military aid. It was drafted in Wehlau and signed there by the Brandenburgian and Polish plenipotentiaries and the Habsburg mediator. The second part was a special convention ("Specialis Convention") containing 6 articles, also drafted and signed by the plenipotentiaries and the mediator in Wehlau, which further detailed the alliance and military aid. The third part amended the Wehlau agreement and primarily detailed Polish concessions. Status of Prussia The Duchy of Prussia—where Frederick William I had become fully sovereign by the Brandenburg-Swedish Treaty of Labiau—was likewise accepted by the Polish–Lithuanian Commonwealth to be the sovereign possession of the House of Hohenzollern. However, Ermland (Ermeland, Warmia) was to be returned to Poland. And if the Brandenburgian Hohenzollern dynasty became extinct in the male line, the Prussian duchy was agreed to pass on to the Polish crown. That made Prussian estates have to pay conditional allegiance to an envoy of subsequent Polish kings upon their succession (hommagium eventuale, Eventualhuldigung), and they were released from previous oaths and obligations regarding the Polish crown. The Roman Catholic Church in the former Duchy of Prussia was to remain subordinate to the archbishop of Ermland (Warmia), retain its possessions and income and be granted religious freedom. Military aid Brandenburg-Prussia was obliged to give military aid to Poland