High Quality Content by WIKIPEDIA articles! The East Prussia(n) plebiscite (German: Abstimmung in Ostpreu?en), also known as the Allenstein and Marienwerder plebiscite or Warmia, Masuria and Powisle plebiscite (Polish: Plebiscyt na Warmii, Mazurach i Powislu), was a plebiscite for self-determination of the regions Warmia (Ermland), Masuria (Mazury, Masuren) and Powisle, which had been in parts of East Prussia and West Prussia, in accordance with Articles 94 to 97 of the Treaty of Versailles. Prepared during early 1920, it took place on 11 July 1920. The plebiscite was conducted by German authorities. According to Richard K. Debo at the time, both German and Polish governments believed that the outcome of the plebiscite was decided by the ongoing Polish-Bolshevik War which threatened the existence of the newly formed Polish state itself and, as a result, even many Poles of the region voted for Germany out of fear that if the area was allocated to Poland it would fall under Soviet rule....