at the same time a major loss for Poland which had become a landlocked country. Thus, the takeover triggered a series of conflicts between Poland and the Teutonic Order, and these conflicts in turn triggered a conflict within the order itself. Some prominent brethren favoured a concession of Pomerelia in exchange for good relations with Poland, but were opposed by a majority of the knights who thought that such a concession would eventually lead to the total expulsion of the knights from their state. These disagreements caused the abdication of Grand Master Charles of Trier in 1318 and the murder of the succeeding Grand Master Werner of Orseln in 1330. The possession of Danzig and Pomerelia by the Teutonic Order was questioned consistently by the Polish kings Władysław I and Casimir the Great in legal suits in the papal court in 1320 and 1333. Both times, as well as in 1339, the Teutonic Knights were ordered by the Pope to return Pomerelia and other lands back to Poland, but did not comply. As a result, in the late 1330s, a war ensued. Peace was established in the Treaty of Kalisz in 1343; although the Polish kings were able to retain the title "Duke of Pomerania" and were recognized as titular overlords of the crusaders, the Knights retained control of Danzig. - this time, with the permission of the papal court. Development of the city stagnated after its capture by the Teutonic Knights. Initially the new rulers tried to reduce the economic significance of Danzig by abolishing the local government and the privileges of the merchants. This was exemplified by the fact that the city council, including Arnold Hecht and Conrad Letzkau, was removed and beheaded in 1411. Later the Knights were forced to accept the fact that city defended its independence and was the largest and most important seaport of the region after overtaking Elbing. Subsequently, it flourished, benefiting from major investment and economic prosperity in the Monastic state and Poland, which stimulated trade along the Vistula. The city had become a full member of the merchant association, the Hanseatic League by 1361, but its merchants remained resentful at the barriers to trade up the Vistula river with Poland, along with the lack of political rights in a state ruled in the interest of the Order's religiously motivated knight-monks. As a result, the city became a co-founder of the Prussian