Kakuei Tanaka in the context of "Niigata Prefecture"

The Liberal Democratic Party (LDP; Japanese: 自由民主党, romanized: Jiyū-Minshutō), also known as Jimintō (自民党), is a major conservative and nationalist political party in Japan. Since its foundation in 1955, the LDP has been in power almost continuously—a period called the 1955 System—except from 1993 to 1996, and again from 2009 to 2012.

The LDP was formed in 1955 as a merger of two conservative parties, the Liberal Party and the Japan Democratic Party, and was initially led by prime minister Ichirō Hatoyama. The LDP supported Japan's alliance with the United States and fostered close links between Japanese business and government, playing a major role in the country's economic miracle from the 1960s to early 1970s and subsequent stability under prime ministers including Hayato Ikeda, Eisaku Satō, Kakuei Tanaka, Takeo Fukuda, and Yasuhiro Nakasone. Scandals and economic difficulties led to the LDP losing power in 1993 and 1994, and governing under a non-LDP prime minister from 1994 before regaining power in 1996. In 1999, the LDP entered into a coalition with Komeito.

Takeo Fukuda (福田 赳夫, Fukuda Takeo; 14 January 1905 – 5 July 1995) was a Japanese politician who served as prime minister of Japan from 1976 to 1978.

Born in Gunma Prefecture and educated at Tokyo Imperial University, Fukuda served as an official in the Ministry of Finance for two decades before entering politics. He was first elected to the Diet in 1952, and served as agriculture, forestry, and fisheries minister in 1959–1960 under Nobusuke Kishi, as head of the party's political affairs section under Hayato Ikeda, and as finance minister (1965–1966, 1968–1971) and foreign minister (1971–1972) under Eisaku Satō, becoming his protégé. Fukuda's political life was marked by a rivalry with Kakuei Tanaka, who succeeded Satō as prime minister in 1972 and under whom Fukuda served as finance minister from 1973 to 1974. As prime minister from 1976, Fukuda formulated the Fukuda Doctrine, which pledged trust and cooperation with Asian countries, and concluded the Treaty of Peace and Friendship between Japan and China in 1978. He was succeeded as premier in 1978 by Masayoshi Ōhira.

Yasuhiro Nakasone (中曽根 康弘, Nakasone Yasuhiro; 27 May 1918 – 29 November 2019) was a Japanese politician who served as Prime Minister of Japan from 1982 to 1987. His political term was best known for pushing through the privatization of state-owned companies and pursuing a hawkish and pro-United States foreign policy.

Born in Gunma Prefecture, Nakasone graduated from Tokyo Imperial University and served in the imperial navy during the Pacific War. After the war, he entered the National Diet in 1947 and rose through the ranks of the Liberal Democratic Party, serving as chief of the Defense Agency from 1970 to 1971 under Eisaku Satō, international trade and industry minister from 1972 to 1974 under Kakuei Tanaka, and administration minister from 1980 to 1982 under Zenkō Suzuki. As prime minister, he passed large defense budgets and controversially visited the Yasukuni Shrine. A conservative contemporary of U.S. president Ronald Reagan, Nakasone privatized the Japanese National Railways and telephone systems, and favored closer ties with the U.S., once calling Japan an "unsinkable aircraft carrier". After leaving office in 1987, he was implicated in the Recruit scandal, causing the influence of his LDP faction to wane before he retired from the Diet in 2004.

Masayoshi Ōhira (大平 正芳, Ōhira Masayoshi; 12 March 1910 – 12 June 1980) was a Japanese politician who served as prime minister of Japan from 1978 until his death in 1980.

Born in Kagawa Prefecture, Ōhira worked in the Ministry of Finance from 1936, and served as the private secretary to Hayato Ikeda, finance minister from 1949 to 1952. Ōhira was first elected to the Diet in 1952, and served as foreign minister in Ikeda's cabinet from 1962 to 1964 and as international trade and industry minister from 1968 to 1970 under Eisaku Satō. He took over Ikeda's faction of the Liberal Democratic Party and later served as foreign minister from 1972 to 1974 under Kakuei Tanaka and as finance minister from 1974 to 1976 under Takeo Miki. He succeeded Takeo Fukuda as LDP president and prime minister in 1978. After his government was defeated in a no-confidence vote, Ōhira decided to call the 1980 election rather than resign, but died suddenly of a heart attack. He is the most recent Japanese premier to die in office.

Tsutomu Hata (羽田 孜, Hata Tsutomu; 24 August 1935 – 28 August 2017) was a Japanese politician who briefly served as prime minister of Japan in 1994.

Born in Tokyo, Hata graduated from Seijo University and was first elected to the National Diet in 1969. He rose to become a key member of the Liberal Democratic Party's Tanaka/Takeshita faction, and served as agriculture, forests, and fisheries minister in the 1980s and finance minister from 1991 to 1992. After Keizō Obuchi took over the faction, Hata formed the Japan Renewal Party in 1993, which joined in the anti-LDP coalition which formed Morihiro Hosokawa's government. Hata served as foreign minister, then replaced Hosokawa as prime minister when he resigned. However, the Japan Socialist Party soon left the coalition, causing it to collapse. Hata lost leadership of his party when it merged with the New Frontier Party, then formed his own Sun Party, which in turn merged with the Good Governance Party then Democratic Party in 1998. Hata became secretary-general of the party, and remained one of its senior advisors until his death.