With the end of World War I, the old international system was torn down, Europe was reorganized, and a new world was born. The European nations that had fought in the Great War emerged economically and socially crippled. Economic depression prevailed in Europe for much of the inter-war period, and debtor nations found it impossible to pay their debts without borrowing even more money, at higher rates, thus worsening the economy to an even greater degree. Germany especially was destroyed economically by World War I and its aftermath: the reparations to Britain and France forced on Germany by the Treaty of Versailles were impossibly high.
The League of Nations represented an effort to break the pattern of traditional power politics, and bring international relations into an open and cooperative forum in the name of peace and stability. However, the League never grew strong enough to make a significant impact on politics, and the goals of deterrence of war and disarmament were left unaccomplished.
The political atmosphere of the inter-war years was sharply divided between those who thought the extreme left could solve Europe's problems, and those who desired leadership from the extreme right. There were very few moderates, and this situation kept the governments of Britain, France, and Eastern Europe in constant turmoil, swinging wildly between one extreme and the next. Extreme viewpoints won out in the form of totalitarian states in Europe during the inter-war years, and communism took hold in the Soviet Union, while fascism controlled Germany, Italy and Spain.
The extremist nature of these disparate ideologies turned European politics into an arena for sharp conflict, erupting in Spain during the late 1930s in the form of the Spanish Civil War, after which Francisco Franco became dictator. In Germany, Adolf Hitler's fascist Nazi Party came to power during the 1930s and prepared once again to make war on Europe. With Britain and France tied up in their own affairs, the path to World War II lay clear.