World War 1 was a significant conflict that lasted from 1914 to 1918. It involved many of the world's major powers, and it had a profound impact on the world. The war saw the downfall of several empires, including the Russian, German, and Austro-Hungarian empires, and it led to the rise of new countries, such as Czechoslovakia, Yugoslavia, and the Kingdom of Serbs, Croats, and Slovenes (which later became known as Yugoslavia). The war also had a significant impact on the political landscape of Europe, and it contributed to the rise of fascism and the start of World War 2. In addition, the war had a significant impact on the global economy, and it led to the creation of new international organizations, such as the League of Nations, which was established to promote international cooperation and prevent future wars.