World War 1, came to an end in 1918 and it had a major impact on world. 1.Empires have come to end , Austria-Hungary, German, Russia and Ottoman.
2.League of Nations was setup, so that, this situation will not be faced again by humanity.
3.Rise of new ideologies, Fascism was on rise in Italy, Communism was prevailing in Russia.
4. Rise of USA as super power, prior to the Great War(aka WW1) USA wasn't so powerful , post war while other super power nations became weak with the war, USA became a super power nation.
5. Technological developments, all the countries racing for armaments tried to beat the other country and so technology was being developed, new guns and gas masks were used for the first time, during the war.