South Korea–United States relations
Following Japanese surrender at the end of the Second World War, the Allied Powers divided the Korean peninsula along the 38th Parallel with two occupation zones with the United States in the south, and the Soviet Union in the north that would later become North Korea. On August 15, 1948, the southern half of Korea declared independence as the Republic of Korea with Syngman Rhee as president. The United States recognized the Republic of Korea as an independent state on January 1, 1949 and diplomatic relations between two countries were established on March 25 in the following year.
Cross-border skirmishes and raids at the 38th Parallel escalated into open warfare when the North Korean forces invaded South Korea on June 25, 1950. The Korean War broke out when North Korea invaded South Korea. In response, 16 member countries of the United Nations, including the United States, came to the defense of South Korea. It was the first significant armed conflict of the Cold War with extensive deployment of American and other troops.
Coup d'état of May Seventeenth
On October 26, 1979, the former president of South Korea of the time, Park Chung-hee, was assassinated by the leader of the Korean Central Intelligence Agency (KCIA). Following the death of the former president, South Korea entered a state of transition. Times prior to the death of Park Chung-hee, was void of democracy and South Korea was an autocratic state. After the assassination, a revision to change South Korea into a nation of democracy was attempted to be implemented. Choi Kyu-hah, who was the prime minister of the time, became the successor of Park Chung-hee and was appointed the role of acting president. With Choi Kyu-ha in power, restricting regulations of the rule of Park Chung-hee were repealed and opposition leaders and activists, such as Kim Dae-jung, were freed from restraint. Choi Kyu-ha later became the official president of South Korea on December 6, 1979. Despite the attempt to change South Korea from an autocratic state to a democratic nation, the already established ideals stemming from the Yushin Constitution, such as martial law and dictatorial rule, was failed to be abolished and an authoritarian rule of the military remained.