What methods have the 3 Kim rulers used to hold power in North Korea?

 In 1948, Kim came to rule the North after the end of Japanese rule in 1945 split the region. By the 1980s, Kim developed a cult of personality closely tied to their state philosophy of Juche, which would later be passed on to his two successors: son Kim Jong-il and grandson Kim Jong-un.

 Coming to power after the end of Japanese rule in 1945, he authorized the invasion of South Korea in 1950, triggering an intervention in defense of South Korea by the United Nations led by the United States. Following the military stalemate in the Korean War, a ceasefire was signed on 27 July 1953.

Explanation:

there ya go mate ^^