This war was the product of conflicting ideologies between Democracy and Communism and was one of the moments when what was known as the cold war got hot. After WW2, Japan had been expelled from Korea and it had been split into North and South with the North being held by China and the South by America. Each setup a government based on its own way of thinking. When both left Korea the North invaded the South. In order to curb the spread of Communism, the UN, led by the United States, helped the South Koreans fight back. China joined in aiding the North.