Itō Hirobumi in the context of "Treaty of Shimonoseki"

The Meiji era (明治時代, Meiji jidai) was an era of Japanese history that extended from October 23, 1868, to July 30, 1912. The Meiji era was the first half of the Empire of Japan, when the Japanese people moved from being an isolated feudal society at risk of colonization by Western powers to the new paradigm of a modern, industrialized nation state and emergent great power, influenced by Western scientific, technological, philosophical, political, legal, and aesthetic ideas. As a result of such wholesale adoption of radically different ideas, the changes to Japan were profound, and affected its social structure, internal politics, economy, military, and foreign relations. The period corresponded to the reign of Emperor Meiji. It was preceded by the Keiō era and was succeeded by the Taishō era, upon the accession of Emperor Taishō.

The rapid modernization during the Meiji era was not without its opponents, as the rapid changes to society caused many disaffected traditionalists from the former samurai class to rebel against the Meiji government during the 1870s, most famously Saigō Takamori, who led the Satsuma Rebellion. However, there were also former samurai who remained loyal while serving in the Meiji government, such as Itō Hirobumi and Itagaki Taisuke.

The First Itō Cabinet is the first Cabinet of Japan led by Itō Hirobumi from December 22, 1885 to April 30, 1888. The cabinet composed of ministry heads replaced the Daijō-kan.  

The Rikken Seiyūkai (立憲政友会; Association of Friends of Constitutional Government) was one of the main political parties in the pre-war Empire of Japan. It was also known simply as the Seiyūkai.

Founded on September 15, 1900, by Itō Hirobumi, the Seiyūkai was a pro-government alliance of bureaucrats and former members of the Kenseitō. The Seiyūkai was the most powerful political party in the Lower House of the Diet of Japan from 1900 to 1921, and it promoted big government and large-scale public spending. Though labeled "liberal" by its own members, it was generally conservative by modern definitions. It often opposed social reforms and it supported bureaucratic control and militarism to win votes. It viewed the Rikken Minseitō as its main rival.

Prince Saionji Kinmochi (Japanese: 西園寺 公望; 7 December 1849 – 24 November 1940) was a Japanese statesman and diplomat who twice served as Prime Minister of Japan, in 1906–1908 and 1911–1912. He was the last surviving member of the genrō, the small group of unofficial elder statesmen who dominated Japanese politics during the Meiji and Taishō periods. As a member of the Kyoto court nobility (kuge), Saionji forged a close relationship with the imperial house from a young age and participated in the Boshin War that overthrew the Tokugawa shogunate. He spent nearly a decade studying in France, where he became a heartfelt Francophile deeply influenced by European liberalism.

Upon his return to Japan, Saionji held a series of high-ranking posts in the Meiji government, including diplomat and cabinet minister, often under the patronage of Itō Hirobumi. In 1903, he succeeded Itō as president of the Rikken Seiyūkai political party and entered into a political compromise with his rival, General Katsura Tarō. For the next decade, a period known as the Keien era, the two men alternated as prime minister, with Saionji leading cabinets from 1906 to 1908 and again from 1911 to 1912.