The Treaty of Versailles did four different significant things to Europe:
1. It blamed the Germans for the war and treated them as if they had been defeated. In fact, the war ended with a ceasefire; no victory or defeat. But Germany was loaded with punitive reparations to be paid to to [mainly] the French in gold, agricultural produce, iron and steel stocks, coal, motor engines, gasoline, timber, leather and so on. The result was poverty and starvation in Germany, which led to the rise of National Socialism.
2. It ended the monarchies in German, Austria and Turkey. It forced on these countries a form of democracy that was unknown in Europe, and loosely based on an American idea. But these countries had no history of representative government on the American congressional model. It was doomed to fail. Within 5 years, these countries experienced revolutions and all Europe came to the verge of another war in which Communism was a major force.
3. New countries were formed in Poland and Czechoslovakia; and re-established in Eastern Europe in Bulgaria, Roumania and in the Balkans. These countries were simply carved out of the pre-war empires. Inevitably, these became the targets for National Socialists after 1933 when the party gained power in Germany. Czechoslovakia was annexed in 1938. The invasion of Poland in August 1939 precipitated WW2.
4. The League of Nations was set up "...to prevent another war from ever breaking out in Europe."