The treaty signed at the “Paris Peace Conference” created new states and changed the borders of some countries. This led inevitably to a dispute between some countries for land.
The League said that it should belong to Finland and finally Sweden accepted.
Both Poland and Germany were borders of Upper Silesia, a region between Poland, Germany and Czechoslovakia, so as Poland and Germany wanted the territory a dispute started.
Finally the problem was taken to the League of Nations and they decided to make a “Plebiscite” (legal process that is solved by being submitted to popular vote a law or an issue of special importance to the state) between the people of the region and the territory was divided in a German side and a Polish side.
It was a dispute between Finland and Sweden over the Aaland Islands. As the both of them had shores to the Baltic they wanted the Aaland Islands they entered on a dispute that was taken to the League.