Park Chung Hee had served as the leader of South Korea since July 1961, during which he was a de facto military dictator and maintained his near-absolute power through legal and illegal channels.

Park originally came to power as Chairman of the Supreme Council of National Reconstruction two months after the May 16 coup (which he had led) overthrew the Second Republic of Korea.

The Supreme Council established a provisional military junta government that prioritized the economic development of South Korea, but faced strong pressure from the United States to restore civilian rule.

In 1963, Park abdicated from his military position to run as a civilian in the October 1963 presidential election, defeating the incumbent President Yun Posun and inaugurating the Third Republic of Korea two months later in December.

On 26 October 1979, Park was assassinated at a safehouse by Kim Jae-gyu, the director of the Korean Central Intelligence Agency (KCIA), causing political turmoil in South Korea.

Although Chun gradually dismantled the highly centralized government structures set up by Park, his presidency was plagued by public outrage over his reaction to the Gwangju Uprising in 1980.

Chun reorganized the government system and created numerous new ministries, but South Korea remained a de facto one-party state under the Democratic Justice Party, and most elections during this era were not considered legitimate.

[2] The NKDP became the opposition in the National Assembly after strong success in the 1985 South Korean legislative election, with only 6% fewer votes than Chun's Democratic Justice Party.

[citation needed] However, in 1986 the NKDP experienced internal ideological conflicts over the severity of opposition to Chun, and in 1987 Kim Young-sam's faction split to form the Reunification Democratic Party.

Bak, a student at Seoul National University and democracy movement activist, died from causes related to police torture after being arrested at a protest.

In 1986, Hyundai Motors began exporting the Pony and Excel models to the United States, the first signal that South Korea was competing with developed countries in the automobile industry.

However, the government's policies provided a favorable environment for large companies, while the rural economy was seriously damaged by the importation of cheap foreign agricultural products.

The Fifth Republic openly maintained close relations with the United States and Japan under the banner of anti-communism, promoting a Korea-US-Japan Triangular Alliance.

Three North Korean agents detonated a bomb at the Martyrs' Mausoleum intending to kill Chun during a wreath laying ceremony to commemorate Aung San.

The Fifth Republic also began to establish diplomatic relations with various African and Asian countries, including the United Arab Emirates, Lebanon, Pakistan, Brunei, and Bhutan.