Mazowsze Zachodnie wobec Zakonu Krzyżackiego w latach 1381-1411

The author presents in this article mutual connections between West Mazowsze and the Teutonic Order in years 1381-1411. The politics of West Mazowsze in this period can be identified with politics of prince Siemowit IVth. After his father's death in 1381 he became a ruler of the following lands: płocka, zawkrzeńska, rawska, gostynińska, sochaczewska and wiska. Prince Siemowit IVth remained neutral and even friendly before the Teutonic Order for a long time. In years 1382-1385 prince participated in fight for Polish throne. From 1386 he was considered to be a confederate of King Władysław Jagiełło. He took part in discourses (negotiations) with the Teutonic Order as a plenipotentiary of Polish king. In spite of this, relations with the Teutonic Order were still good. Politics of prince Siemowit IVth was very adequate before King Jagiełło and the Teutonic Order, as well. His main political principle was oscillating between them. It can be concluded, that this kind of politics brought many interests (goods) for Mazowsze land. Siemowit IVth was welcome favourably on the court in Cracow and in Malbork, as well. But situation became very difficult for him when the war between Poland and the Teutonic Order broke out (1409) Prince Siemowit IVth probably did not participate in fighting in that time. He remained neutral. But in the 4th of July 1410 (under the influence of King Jagiełło) he declared war to the Teutonic Order. Then he organised two companies for Grunwald campaigne under his son - Siemowit Vth command. Siemowit IVth also took part in negotiations in Toruń (1411). Summing up, we can say that relations between West Mazowsze and the Teutonic Order were in general proper. There were more periods of friendship and neighbourly co-operation than periods of mutual enmity.