The division of north korea and south korea was caused by a difference in

China, Russia, and Japan set their sights on Korea because of its crucial military placement during WWII. It fell under the power of Japan until the end of WWII. The United Nations divided the country into two separate parts- North Korea and South Korea. North Korea was under the protection of the Soviet Union, and South Korea was under the protection of the United States. After a war was started to try and make South Korea a communist country, a Demilitarized Zone was created at the 38th parallel. To this day, North Korea remains communist and South Korea remains a democracy. So Korea's division was caused by a difference between democracy and communism.