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Rikken Seiyūkai 立憲政友会
Leader	Itō Hirobumi Saionji Kinmochi Hara Takashi Takahashi Korekiyo Tanaka Giichi Inukai Tsuyoshi Suzuki Kisaburō
Founder	Itō Hirobumi[1][2]
Founded	September 15, 1900 (1900-09-15)[3]
Dissolved	July 30, 1940 (1940-07-30)
Merger of	Kenseitō[4] Teikokutō (factions)[4] Kakushin Club (factions, 1925)
Merged into	Imperial Rule Assistance Association[1]
Succeeded by	Seiyūhontō (Mainstream faction, 1924, viaShinsei Club) Shōwakai (pro-Tokonami faction, 1935)
Headquarters	Tokyo City
Newspaper	Seiyūkai[5] Chuo Shimbun (ja)[6]
Ideology	Conservatism (Japanese)[12] Liberal conservatism[1][13] Modified capitalism[14] Monarchism[15] Anti-particracy[16] Faction: Gradualist economics[17] Keynesianism[18][19]
Political position	Centre-right[20] toright-wing[21]
Politics of Japan Political parties Elections

TheRikken Seiyūkai (立憲政友会; Association of Friends of Constitutional Government) was one of the mainpolitical parties in the pre-warEmpire of Japan. It was also known simply as theSeiyūkai.

Founded on September 15, 1900, byItō Hirobumi,^[2] theSeiyūkai was a pro-government alliance of bureaucrats and former members of theKenseitō. TheSeiyūkai was the most powerful political party in theLower House of theDiet of Japan from 1900 to 1921, and it promotedbig government and large-scale public spending. Though labeled "liberal" by its own members, it was generallyconservative by modern definitions. It often opposed social reforms and it supported bureaucratic control andmilitarism to win votes. It viewed theRikken Minseitō as its main rival.

TheSeiyūkai came into power in October 1900 under the 4th Itō administration. Under its second leader,Saionji Kinmochi, it participated in theMovement to Protect Constitutional Government from 1912 to 1913. It was the ruling party under thePrime MinisterYamamoto Gonnohyōe from 1913 to 1914. Cabinet minister (and later 4th party president)Takahashi Korekiyo helped reinforce its ties with thezaibatsu, especially theMitsui financial interests.

The 3rd party president,Hara Takashi, became Prime Minister in September 1918, and assigned every cabinet post except for theArmy Minister,Navy Minister andMinister of Foreign Affairs to members of theSeiyūkai. In 1920, the party reached the peak of its popularity.

After Hara's assassination in 1921, a large block of party members defected to form theSeiyūhontō in the1924 General Election; however, theSeiyūkai retained enough seats to dominate the cabinet of its 5th party president, GeneralTanaka Giichi from 1927 to 1929.

While in the opposition during theMinseitō-dominated cabinet of Prime MinisterHamaguchi Osachi, theSeiyūkai attacked the ratification of theLondon Naval Treaty of 1930 as against Article 11 of theMeiji Constitution, which stipulated the independence of the military from civilian control.

After winning the1932 General Election underInukai Tsuyoshi,Seiyūkai formed a cabinet, floated theyen and conducted policies to revive the economy. However, after Inukai’s assassination in theMay 15 Incident of 1932, factionism within the party limited its effectiveness.

In 1940, it voted to dissolve itself into theImperial Rule Assistance Association as part ofFumimaro Konoe's efforts to create aone-party state, and thereafter ceased to exist.

Ichirō Hatoyama, who had been aSeiyūkai member of the House of Representatives, led some former party members into the 1945Liberal Party.

Orthodox faction - also known as theKuhara faction (centered around Hatoyama, Kuhara, Mitsudo, Yoshizawa, and Takuji Hida).

Reformist faction - also known as theNakajima faction, formally known as theRikken Seiyukai Reform Alliance (centered around Nakajima, Maeda, Shimada, Tanabe Shichiro, and Togo Makoto).

Neutral -Konko faction (Konko, Inukai, Ota, etc. at the center). Developed into the unification faction.

Election	Votes	%	Seats	+/–
1902	433,763	50.40%	191 / 376
1903	373,022	45.42	175 / 376	16
1904	217,691	33.47	133 / 379	42
1908	649,858	48.40	187 / 379	54
1912	689,613	51.52	209 / 381	22
1915	446,934	31.54	108 / 381	101
1917	504,720	38.80	165 / 381	57
1920	1,471,728	55.77	278 / 464	113
1924	666,317	22.41	103 / 464	175
1928	4,244,385	43.06%	217 / 466	114
1930	3,925,980	37.69	174 / 466	43
1932	5,683,137	58.20	301 / 466	127
1936	4,188,029	37.62	174 / 466	127
1937	3,594,863	35.23	175 / 466	1

• Inoue, Toshikazu[in Japanese] (2012).Seiyūkai to Minseitō: senzen no nidai seitōsei ni nani o manabu ka. Chuko Shinsho (in Japanese). Tokyo:Chuokoron-Shinsha.ISBN 978-4-12-102192-2.

• Defunct conservative parties
• Defunct political parties in Japan
• Conservative parties in Japan
• Liberal conservative parties
• Political parties established in 1900
• Political parties disestablished in 1940
• Political parties in the Empire of Japan
• 1900 establishments in Japan
• 1940 disestablishments in Japan

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