The Author analyzes the use of political violence in Poland before and after the First World War. In particular, he focuses on the activities of the main political parties and the use of violence against the Jewish minority. The main causes of the continued political use of violence are individuated in the weakness of the international community at the time and the growing nationalism in the states born from the collapse of the central empires. In the opinion of the author the inability of the winners of the war to solve the problem of minorities and the pending issue of borders of the new states as well as the spread fear of communism, expressed by frequent strikes and revolts of workers, have contributed to nurturing this violence. In Poland, reborn after the war, the main political parties used political violence to achieve their goals and, thus, created the conditions for the assassination of the first president of the Polish Republic.