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        World War I or the First World War was a global conflict fought between two coalitions. - 
  
  
        The Great Depression was a severe global economic downturn that affected many countries across the world. - 
  
  
        The European Union is a geo-political entity covering a large portion of the European continent. - 
  
  
        World War II was the biggest and deadliest war in history, involving more than 30 countries. - 
  
  
        The Holocaust was the genocide of European Jews during World War II. - 
  
  
        Proposed that the United States provide economic assistance to restore the economic infrastructure of postwar Europe. - 
  
  
        With the closing of the East-West sector boundary in Berlin, the vast majority of East Germans could no longer travel or emigrate to West Germany. - 
  
  
        The Cuban missile crisis was a major confrontation in 1962 that brought the United States and the Soviet Union close to war over the presence of Soviet nuclear-armed ballistic missiles in Cuba. - 
  
  
        At a press conference on 9 November, East German spokesman Günter Schabowski announced that East Germans would be free to travel into West Germany, starting immediately. - 
  
  
        The unsuccessful August 1991 coup against Gorbachev sealed the fate of the Soviet Union.