The commotion was traced to a narrow alley in Seoul’s Gungjeong-dong neighborhood, near the Blue House—South Korea’s presidential residence. Director Kim Jae-gyu of the Korean Central Intelligence Agency (KCIA) had opened fire on Park Chung-hee, the president of South Korea, ending Park’s life and the authoritarian regime that had been the Fourth Republic of Korea.

Park’s military regime first came into power in 1961. It proceeded to retain a viselike grip on South Korea for eighteen years by amending the constitution three times, ultimately allowing an individual to remain in office for an indefinite number of terms. In October 1972, the regime declared martial law and illegally passed the Fourth Republic Constitution (also known as the Yusin Constitution), signaling the start of a decade of cruel military dictatorship.¹ Chaebol monopolies were formed under the regime’s protection, leading to worsened economic exploitation and increased pressure on the working class. In the midst of mounting authoritarian oppression, postsecondary students and some intellectuals began to form organized resistance groups. It was in this time of merciless tyranny that the South Korean democratization movement developed and grew.

However, much of the resistance in the 1970s was limited to the students and intellectuals, with little participation from agricultural- and industrial-sector workers. The Yusin regime responded to fledgling attempts at activism by promoting ideologies such as economic development and anti-communism to tighten its control over society. Its plan to spur economic development indeed found quantitative success but led directly to problems such as low incomes, growing urban poverty rates, the dissolution of agricultural communities, widening wealth gaps, and regional development gaps. The social pressures eventually reached a breaking point marked by the Busan-Masan Democratization Protests.

The protests began on October 16, 1979, as a demonstration by students in the city of Busan calling for the end of the Yusin regime. They were quickly joined by blue-collar workers and ordinary citizens from the neighboring city of Masan. The demonstration quickly turned into a full-fledged protest. On October 18, Park Chung-hee declared martial law in the Busan area and court-martialed sixty-six civilians. Two days later, on October 20, Park declared a garrison decree over the Masan and Changwon regions—deploying tanks and the 3rd Airborne Special Forces Brigade to quash the protests—and court-martialed fifty-nine civilians. The Busan-Masan Democratization Protests were thus stopped, but the trigger had already been pulled. Less than a week later, the Yusin regime ended with the assassination of Park Chung-hee.

On October 26, Park attended the opening ceremony of a dam in Sapgyocheon, South Chungcheong Province, and returned to Seoul for dinner in Gungjeong-dong. The meal was well underway and the diners relaxing over a bottle of Chivas Regal when an argument began between Kim Jae-gyu and chief presidential bodyguard Cha Ji-chul over the regime’s response to the protests. Where Cha was in full agreement with the strong military retaliation, Kim argued that displays of forceful oppression would not sustain the regime much longer. Cha went as far as to respond, “Pol Pot of Cambodia stayed in power after killing two million people; we could easily kill one million and retain our authority.” Park sided with Cha in the matter. Kim judged that the Yusin regime had to be ended,² took out a handgun, and shot Park and Cha.

President Park Chung-hee, symbol of the authoritarian Yusin regime, was suddenly removed from the throne. In that instant, South Korean politics was turned upside down. The regime had stood on five pillars of political power—the KCIA, the presidential secretariat, the presidential security service, the military, and the Blue House (South Korea’s executive office and presidential residence), with the latter reigning at the top. The assassination resulted in all but the military losing political authority.³

To minimize the incident’s effect on the public, the government focused its efforts on maintaining order and setting the foundations for the gradual development of the political system.⁵ The foreign press took note of the swift response and commented, “daily life for South Korean citizens is quickly returning to business as usual” and that citizens were “expected to shape a new republic founded on the bedrock of political freedom” in a show of optimism for the country’s future.⁶ On November 8, Acting President Choi delivered a state of affairs address promising the amendment of the Yusin Constitution and a government-led move to democratization. The interim government’s rapid response led to the equally rapid pacification of public sentiment.

The US government also reacted quickly to the assassination.⁷ In the immediate aftermath of the killings, President Jimmy Carter convened the National Security Council and declared DEFCON 3 for United States Forces Korea (USFK). Deeming that intervention by North Korea, the USSR, and China was likely, the US State Department warned them not to take action. As outlined in the Mutual Defense Treaty between the Republic of Korea (ROK) and the United States, the US military responded promptly. On October 28, US Secretary of Defense Harold Brown deployed two state-of-the-art Airborne Warning and Control System (AWACS) units as a deterrent. Two days later, the USS Blue Ridge, flagship of the United States Seventh Fleet with a displacement of over 12,000 tons, was stationed at the Port of Busan. On November 2, the USS Kitty Hawk, a supercarrier with a displacement of 73,000 tons, as well as two guided missile cruisers, were stationed at the same port, and three pairs of battleships (including frigates) were deployed to the ports of Jinhae and Incheon. The United States Pacific Command (PACOM) firepower was focused on the Korean Peninsula to serve as a powerful bulwark.⁸ The proactive defensive maneuver was powerful enough to raise tensions not only in North Korea but also in China and the USSR. The increased security made the possibility of North Korean invasion or infiltration of South Korea practically impossible.⁹

President Carter continued to keep a close eye on the situation in South Korea, forming a policymaking group in the National Security Council.¹⁰ This team was dubbed “Cherokee”¹¹ and convened to directly discuss South Korea and decide on policies for the country. Members included President Carter and US Secretary of State Cyrus Vance, with US Ambassador to South Korea William H. Gleysteen being the only member based in the country. Gleysteen would keep in contact with South Korean officials like Defense Security Commander Chun Doo-hwan, President Choi Kyu-hah, ROK-US Combined Forces Command Deputy Commander Lew Byeong-hyun, Prime Minister Shin Hyun-hwak, and Minister of Foreign Affairs Pak Tongjin. His role was to discreetly represent US interests and negotiate with South Korean officials.

On December 6, Acting President Choi was formally elected president by the National Conference for Unification, a 2,549-member electoral college. Politicians across the spectrum suspected that the acting Choi administration intended to carry on an updated version of the Yusin regime. The regime’s supporters remained in positions of absolute national influence and hoped to drag their feet, waiting for public sentiment to settle again before pursuing an advantageous new constitution. The YWCA meeting and Choi’s election to office were signs of turbulent times to come. The future of South Korea was mired in complete political uncertainty.

Threatened with removal from positions of political influence, the Hanahoe chose to turn the tables by seizing military command. Its first target was Chief of Staff Jeong Seung-hwa. Chun led the conspiracy, assisted by Defense Security Command advisors including Chief Secretary Heo Hwa-pyeong, Chief of Personnel Heo Sam Soo, and Chief Investigator Lee Hak-bong—all members of the Hanahoe. The group went so far as to draft plans for a military command overhaul and administrative takeover, which would be implemented upon the success of the insurrection.¹⁴

In early December, Chun commanded Lieutenant Colonel Lee Hak-bong to devise a plan for the arrest of Chief of Staff Jeong Seung-hwa, citing Jeong’s dubious actions during the Park assassination.¹⁵ His preparations complete, Chun met with Commander Roh Tae-woo of the 9th Infantry Division on December 7 and set December 12 as the date of the coup.

On the evening of December 12, core members of the Hanahoe—Yu Hak-seong, Hwang Young-si, Cha Gyu-heon, Park Jun Byung, Baek Un-taek, Park Hee-do, Choi Se-chang, Jang Gi-oh, Jang Se-dong, and Kim Jin-young—discreetly convened at the office of the 30th Garrison at Capital Garrison Command. In the meantime, Roh withdrew the 9th Infantry Division from the front lines, deploying them to Seoul in a flagrant violation of the law. Park Hee-do and Choi Se-chang deployed the paratroopers under their command to the capital as well. Heo Sam Soo, chief of personnel at Defense Security Command, launched an assault on the chief of staff’s official residence and, following a shootout with security, took Jeong Seung-hwa into custody. Upon receiving belated news of the arrest, commanders such as Special Warfare Commander Major General Jeong Byeong-ju, Capital Garrison Commander Major General Jang Tae-wan, and ROK Army Provost Marshal General and Martial Law Command Public Security Chief Brigadier General Kim Jin-gi mobilized their forces. However, the insurrectionists had already taken the upper hand.¹⁶

Having taken the ROK Army chief of staff into custody, Chun Doo-hwan went to President Choi Kyu-hah to request his official approval for the arrest. Choi responded with rage. “You’ve made a complete mess. This is a breach of protocol. It is illegal, and I will not give my approval without listening to the circumstances first. I demand to see the Minister of National Defense.” At 3:30 a.m., the insurrectionists emerged victorious in a shootout and took control over the ROK Army HQ and the Ministry of National Defense. Finally, they hauled Minister of National Defense Roh Jae-hyeon to Defense Security Command, and at 5:00 a.m., Chun took him to the Blue House. President Choi put his signature at the bottom of the approval document, adding the time of the signature—5:00 a.m.—to indicate that he had resisted for as long as he could.¹⁷

Because of the speed at which the events unfolded, little about the December 12 military insurrection was known to the public. Although tanks were deployed and soldiers exchanged fire in the streets of Seoul—leaving a significant number of personnel dead—very few outside those directly involved recognized the dramatic change. The fact that the incident took place at night and involved so few people meant that the coup and its immediate ramifications remained nearly imperceptible even to the government and those in the political world who had been keeping a close eye on the political situation.

The December 12 military insurrection involved the unlawful deployment of over 5,000 personnel and thirty-five tanks. A regular combat unit at the frontlines against North Korea had left its post and entered Seoul, and the official chain of command at the ROK Army HQ was left completely paralyzed. The incident was met with strong criticism from the United States, which claimed that the deployment of the 9th Infantry Division from the North Korean border to Seoul without the prior consent of the ROK-US combined forces commander was a violation of the Mutual Defense Treaty.¹⁸ The following day, Chun retrieved public funds from the vault at the Ministry of National Defense and handed out KRW 50 million to each unit that was ordered to participate in the coup as though dividing spoils of war.

On the morning after the coup, the insurrectionists immediately shuffled key military positions, seating Hanahoe members or pro-Chun personnel in places of command. Choo Young-bock was made minister of national defense, Lee Hui-seong the ROK army vice chief of staff, Roh Tae-woo the capital garrison commander, and Chung Ho-yong the special warfare commander. The unofficial organization seized full control over the military, giving rise to the Singunbu regime. Only two days after the coup, Gleysteen met Chun at the US embassy. According to a recent WikiLeaks cable, the Chun-Gleysteen meeting was arranged by CIA station chief in South Korea Robert Brewster, despite opposition by ROK-US Combined Forces Commander John Wickham. The United States’ implicit acceptance added further leverage to Chun’s influence over t...