The Bolsheviks could not prevent the independence of the Baltic states, but the West had to be persuaded to accept it. By 1921 Lithuania, and by 1922 Estonia and Latvia, all obtained "de jure" international recognition. All three states joined the League of Nations in 1921. The Baltic states begin to build a regional alliance system with their neighbours in Scandinavia and eastern Europe. In the south, Poland was reconstituted with consolidation of territories from Germany and Russia. Furthermore, in summer 1920, Lithuania cooperated with Bolsheviks trying to seize Vilnius, which poisoned Lithuanian relations with their neighbours. In the north, Finland had also been under Russian control from 1809 until its independence in 1918, but the Finns looked to Scandinavia rather than towards the Baltic states. In the west, Sweden followed a policy of neutrality, but during the 1920s, it took a more active regional role.