Upper Silesia Plebiscite Decides German-Polish Border, March 20, 1921
The Upper Silesia plebiscite, mandated by the Versailles Treaty to determine a section of the border between Weimar Germany and Poland, is held. Date: March 20, 1921 Read more on Wikipedia → 📅 Other events on March 20 📅 Events on this day in 1921 📅 On This Day (Today)