5 and 6

1. 6. At the end of World War II, the governments of the United States and the Soviet Union decided that the Soviet Union would invade the Japanese held territories of mainland Asia south to the 38th Parallel and the United States would invade north to the same point. In 1948,with a failure to unite the two areas, elections were held and the new South Korea came under the power of    Syngman Rhee. Kim Il-sung took power in North Korea. 

On June 25 June, 1950, communist North Korean forces crossed the 38th parallel into democratic South Korea. 

The 38th parallel, as the pre-war boundary between the countries, became the focal point for negotiations of a cease fire. There has been no peace treaty, only a cease fire. The 38th parallel continues to be the most highly defended border in the world across the 3 mile wide Demilitarized Zone (DMZ).

5. North Korea and and the East China Sea border South Korea.