Korean reunification propaganda in at the Demilitarized Zone (DMZ) "Korea is One!". DMZ is the most heavily militarized border in the world, dividing Korea in half. It was the original boundary between the United States-occupied and Soviet-occupied areas of Korea at the end of World War II. Upon the creation of the Democratic People's Republic of Korea (DPRK, informally North Korea) and the Republic of Korea (ROK, informally South Korea) in 1948, it became a de facto international border and one of the most tense fronts in modern time.