The 38th parallel north is a circle of latitude that is 38 degrees north of the Earth's equatorial plane. It crosses Europe, the Mediterranean Sea, Asia, the Pacific Ocean, North America, and the Atlantic Ocean. The 38th parallel north formed the border between North and South Korea prior to the Korean War. Today, it divides Korea into two separate countries.

In 1945 Korea had been divided along the 38th parallel, its industrial north being occupied by the Soviets and the agricultural south by the Americans. ... Soviet and American forces both withdrew, but North Korean forces invaded the south in June 1950 with Stalin's foreknowledge and approval. North and South Korea have been divided for more than 70 years, ever since the Korean Peninsula became an unexpected casualty of the escalating Cold War between two rival superpowers: the Soviet Union and the United States.

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