

After the Second World War, Korean became divided. The Communists ruled its northern part. A non-Communist government ruled its southern part.
  South Korea grew in late 1940s. Finally, a war broke out between the two government 
  in 1950.
  United Nation forces under MacArthur helped South Korea. Chinese volunteers 
  helped North Korea.
  At last, they signed a cease-fire agreement to end the war.