 The Seedienst Ostpreußen was established to provide an independent transport service to East Prussia.On 11 July 1920, amidst the backdrop of the Polish-Soviet War, the East Prussian plebiscite in eastern West Prussia and southern East Prussia was held under Allied supervision to determine if the areas should join the Second Polish Republic or remain in Weimar Germany Province of East Prussia.96.7% of the people voted to remain within Germany (97.89% in the East Prussian plebiscite district).