At the Council of Constance, the issue of the Christianisation of Lithuania and Samogitia came to the fore in the dispute between the Polish-Lithuanian Union and the Teutonic Knights. The whole matter was brought about by a Polish-Lithuanian delegation (1416), which in two indictments, Proposicio Polonorum and Proposicio Samagitarum, accused the Grand Master and the Order of hostility towards the recently baptised Lithuanians and against the Samogitians, who had expressed the same willingness to accept the Catholic faith. On the contrary, the Order's delegation, calling on its own historical experience, accused the dukes of Lithuania, including King Vladislav Jagello of Poland, of hypocrisy, dishonesty and treachery. Surprisingly, the Order's reply does not call into question the very fact of the mass baptism of Lithuanians, who willingly accepted Christianity, but doubted their simple-mindedness and inability to understand the content of the creed and the significance of the ceremony they had undergone. The Polish-Lithuanian party's argument was more successful because it was based on numerous biblical motifs, such as the light and peace that Jesus Christ brought to earth and which were desired by the pagans in Lithuania and Samogitia. On the contrary, the political and historical arguments of the Order's delegation lacked a similar positive emotional charge. The practical long-term consequence of the controversy was the official baptism of the Samogitians, the establishment of a diocese (1417) and the permanent annexation of the disputed territory to Lithuania.
The importance of papal and imperial privileges for the Teutonic Order increased in the conflictual period between the Order and Polonia/Lithuania in the years following 1386, when polish lawyers began to doubt all its privileges on a general base. It's nevertheless surprising that these privileges don't almost show in the medieval historiography of the Order. It's therefore necessary to stimulate further research dedicated to the cartularies and the privilege confirmations under their legal and memorial aspects.
The author analyzes the diplomatic sources related to the negotiations between the Teutonic Knights and the Polish-Lithuanian Union after the truce in October 1414. As the compromise was not agreed within the set two-year period, the truce had to be extended, which was eventually done several times until 1421. Negotiations for the extension of the truce were quite tough. The King of Poland used the threat of non-renewal of the truce to put pressure on the Grand Master who was afraid of resuming war against a powerful adversary. Uncertainty surrounding the extension of the truce forced the Grand Master to hire mercenaries every year in the Empire. He also objected to the July deadline (St. Margaret) for the truce set each year, because this month was the most convenient time to begin a war campaign. Nevertheless the Grand Master refused to hand his three villages of Kujawy, which had formed an enclave on Polish territory, over to the King of Poland. Negotiations sometimes took place in several places simultaneously which caused some communication difficulties. The content of the charters extending the truce was drawn a comparison.