Although mass decolonization was not achieved until after World War II, demands for the liberation of independent nations came much earlier. Supporting this cause was the Pan-African movement, which rose in popularity following World War I. Negotiations for the Peace Treaty of Versailles, which took place from November 1918 to June 1919 and brought an end to the war, focused on self-determination in Europe. This focus allowed organizations like the National Association for the Advancement of Colored People (NAACP) to pose the African question to the political leaders of Europe, who had recently felt the effects of political occupation.