1979 South Korean coup d'état

Background

The assassination of the 3rd President of South Korea, Park Chung Hee, on 26 October 1979 had thrown South Korea into a state of political turmoil. Prime Minister Choi Kyu-hah immediately became acting President and declared a state of martial law across the nation with the exception of Jeju Province. He appointed Chief of Staff of the Army General Jeong Seung-hwa to oversee the operation of martial law. Jeong appointed Major General Chun Doo-hwan, commander of the Defence Security Command to investigate Park's assassination. Jeong, Chun and Chairman of the Joint Chiefs of Staff Kim Jong-hwan were then the most powerful figures in the military.

According to official investigations, President Park's assassin and director of KCIA Kim Jae-gyu had approached Jeong, who was present at the scene of the assassination (though not a witness) to take command of the situation after his assassination, but Jeong refused.

Chun, who harbored political ambitions, was a rival to Jeong, given that the Military Security Command served as a hedge against any potential military coup under President Park. Jeong moved to reassign Chun, Roh Tae-woo, and other members of Hanahoe to less important posts to sideline them and prevent Hanahoe’s rise. Fearing their careers were at stake, Chun and the rest of Hanahoe moved before Jeong could render them politically impotent.

Mutiny

On the evening of 12 December 1979, Chun, acting without authorization from President Choi, ordered the arrest of Jeong on allegations of involvement in the assassination of former President Park. Minister of National Defense Roh Jae-hyun fled from his position and brought his entire family to the Yongsan Garrison to seek protection in the U.S. embassy before being advised to return to duty. After reluctantly returning to the army command, he refused to order the arrest of Chun or other rebel generals. Instead, he ordered the arrest of Jeong to appease the rebels. Shortly thereafter, he withdrew from politics.

After Jeong's capture, the 29th Regiment of the 9th Division, along with the 1st and the 3rd Special Forces Brigade, invaded downtown Seoul to support the 30th and 33rd Capital Security Groups, which were loyal to Chun, resulting in a series of clashes that broke out in the capital. Two of Jeong's allies, Major General Jang Tae-wan (Commander of Army Capital Security Command) and Major General Jeong Byeong-ju (Commander of Army Special Warfare Command), were also arrested by the rebel troops. Major Kim Oh-rang, aide-de-camp of Jeong Byeong-ju, was killed during the gunfight.

By the next morning, the Ministry of Defense and Army Headquarters were occupied by the mutineers. Chun and his fellow graduates of the 11th class of the Korea Military Academy, such as Major General Roh Tae-woo, commanding general of the 9th Infantry Division, and Major General Jeong Ho-yong, were in charge of the Korean ground forces. Chun's mutiny and the subsequent consolidation of power was aided by the powerful private club of military officials known as Hanahoe. The Navy and Air Force did not participate in the mutiny, but Chun subsequently co-opted them following its success. In addition, the only Marine Corps involvement in the coup was by Jeong's residential guards, who engaged in armed confrontation with the 33rd MP. Chun became the de facto commander-in-chief, rather than President Choi Kyu-hah.

Aftermath

Jeong Seung-hua was sentenced to 10 years imprisonment in a court-martial on 13 March 1980, while Jang Tae-wan and Jeong Byeong-ju were forcibly discharged from military service and placed under house arrest. In January 1980, the South Korean military underwent a massive reorganization. Since then, any generals who had made critical remarks about the mutiny, either in public or in private, were either forced to leave their posts or were transferred to other positions.

The mutiny marked the beginning of the end of the Fourth Republic of Korea. The mutiny, the coup d'etat of the civilian government on 17 May 1980, alongside the Gwangju Uprising, was the primary justification for Chun's 1995 arrest by the Kim Young-sam administration.

In 2022, a presidential commission on military deaths reclassified Kim Oh-rang's death during the coup as having been "killed in action" rather than having "died on duty". The redesignation meant that Kim's death was officially attributed to engagement with the enemy or while preventing disturbances to public peace, such as a rebellion. In 2025, the Seoul Central District Court ordered the government to provide 300 million won (US$216,000) in compensation to the Kim's relatives following a lawsuit filed by his family.

Cultural references

Film

• 12.12: The Day (2023)

Television

• 4th Republic (1995–96)
• 5th Republic (2005)
• Koreagate (1995)
• Surprise Mystery TV – 12.12: The Day (2023)

References

References

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