 Faced with Albrecht's rearmament and hostile alliances, Poland waged a war in 1519; the war ended in 1521, when mediation by Charles V resulted in a truce.As a compromise move Albrecht, persuaded by Martin Luther, initiated a process of secularization of the Order and the establishment of a lay duchy of Prussia, as Poland's dependency, ruled by Albrecht and afterwards by his descendants.The terms of the proposed pact immediately improved Poland's Baltic region situation, and at that time also appeared to protect the country's long-term interests.