Chōshū Domain in the context of "Itō Hirobumi"

The Boshin War (戊辰戦争, Boshin Sensō), sometimes known as the Japanese Revolution or Japanese Civil War, was a civil war in Japan fought from 1868 to 1869 between forces of the ruling Tokugawa shogunate and a coalition seeking to seize political power in the name of the Imperial Court.

The war stemmed from dissatisfaction among many nobles and young samurai with the shogunate's handling of foreigners following the opening of Japan during the prior decade. Increasing Western influence in the economy led to a decline similar to that of other Asian countries at the time. An alliance of western samurai, particularly the domains of Chōshū, Satsuma, and Tosa, and court officials secured control of the Imperial Court and influenced the young Emperor Meiji. Tokugawa Yoshinobu, the sitting shōgun, realizing the futility of his situation, abdicated and handed over political power to the emperor. Yoshinobu had hoped that by doing this the House of Tokugawa could be preserved and participate in the future government.

The Mōri clan (毛利氏, Mōri-shi; Japanese pronunciation: [moꜜː.ɾʲi, moː.ɾʲiꜜ.ɕi]) was a Japanese samurai clan descended from Ōe no Hiromoto. Ōe no Hiromoto was descended from the Fujiwara clan. The family's most illustrious member, Mōri Motonari, greatly expanded the clan's power in Aki Province. During the Edo period his descendants became daimyō of the Chōshū Domain under the Tokugawa shogunate. After the Meiji Restoration with the abolition of the han system and daimyō, the Mōri clan became part of the new nobility.

The Government of Meiji Japan (明治政府, Meiji seifu) was the government that was formed by politicians of the Satsuma Domain and Chōshū Domain in the 1860s. The Meiji government was the early government of the Empire of Japan.

Politicians of the Meiji government were known as the Meiji oligarchy, who overthrew the Tokugawa shogunate.

Shishi (志士), sometimes known as Ishin Shishi (維新志士), were a group of Japanese political activists of the late Edo period. While it is usually applied to the anti-shogunate, pro-sonnō jōi (尊皇攘夷; lit. 'Revere the Emperor, Expel the Barbarian[s]') samurai primarily from the southwestern clans of Satsuma, Chōshū, and Tosa, the term shishi is also used by some with reference to supporters of the shogunate, such as the Shinsengumi.

There were many different varieties of shishi. Some, such as the assassins Kawakami Gensai, Nakamura Hanjirō, Okada Izō, and Tanaka Shinbei, opted for a more violent approach in asserting their views. Kawakami Gensai, in particular, is recalled as the assassin of Sakuma Shōzan, a renowned pro-Western thinker of the time. Several assaults on westerners in Japan have been attributed to the shishi and associated rōnin warriors. In a 2013 article, these assassins have been called "early terrorists" (German: frühe Terroristen) since they opted to spread terror among the foreigners. Other more radical shishi, such as Miyabe Teizō, plotted large-scale attacks with little regard for public safety. Miyabe himself was one of the ringleaders of the plot, foiled by the Shinsengumi at the Ikedaya Incident, to burn Kyoto at the height of the Gion Festival.

The Shinsengumi (新選組, "Newly Selected Corps") was a small secret police organization, an elite group of swordsmen organized by commoners and low-ranking samurai, commissioned by the bakufu (military government) during Japan's Bakumatsu period (late Tokugawa shogunate) in 1863. It was active until 1869. It was founded to protect shogunate representatives in Kyoto at a time when a controversial imperial edict to exclude foreign trade from Japan had been made and the Chōshū clan had been forced from the imperial court. They gained considerable fame from events such as the Ikedaya incident and the August 18 coup, among others. The members were drawn from the sword schools of Edo.

The Battle of Toba–Fushimi (鳥羽・伏見の戦い, Toba-Fushimi no Tatakai) occurred between pro-Imperial and Tokugawa shogunate forces during the Boshin War in Japan. The battle started on 27 January 1868 (or fourth year of Keiō, first month, 3rd day, according to the lunar calendar), when the forces of the shogunate and the allied forces of Chōshū, Satsuma and Tosa Domains clashed near Fushimi, a town near Kyoto, the sacred capital, and fighting progressed to the Toba road leading to Osaka, with the initial rout of the Satsuma from Fushimi. The battle lasted for four days, ending in a decisive defeat for the shogunate.

Mutsuhito (睦仁; 3 November 1852 – 29 July 1912), posthumously honored as Emperor Meiji (明治天皇, Meiji Tennō), was the 122nd emperor of Japan according to the traditional order of succession, reigning from 1867 until his death in 1912. His reign is associated with the Meiji Restoration of 1868, which ended the Tokugawa shogunate and began rapid changes that transformed Japan from an isolationist, feudal state to an industrialized world power. Emperor Meiji was the first monarch of the Empire of Japan, and presided over the Meiji era.

At the time of Mutsuhito's birth, Japan was a feudal and pre-industrial country dominated by the isolationist Tokugawa shogunate and the daimyō subject to it, who ruled over Japan's 270 decentralized domains. The opening of Japan to the West from 1854 fueled domestic demands for modernization, and when Mutsuhito became emperor after the death of his father Emperor Kōmei in 1867, it triggered the Boshin War, in which samurai (mostly from the Chōshū and Satsuma Domains) defeated the shogunate and restored power in his name. Documents issued during his reign include the Charter Oath of 1868, Meiji Constitution of 1889, Imperial Rescript to Soldiers and Sailors of 1882, and Imperial Rescript on Education of 1890, in which he was advised by a group of oligarchs known as the genrō. Other major events which occurred during his reign include the establishment of the Cabinet in 1885, Privy Council in 1888, Imperial Diet in 1890, and military victories over China in the First Sino-Japanese War and over Russia in the Russo-Japanese War. Taiwan and Korea were annexed in 1895 and 1910, respectively. Emperor Meiji died in 1912, and was succeeded by his eldest son, Yoshihito.

The Satsuma–Chōshū Alliance (薩摩長州同盟, Satsuma Chōshū dōmei), or Satchō Alliance (薩長同盟, Satchō dōmei) was a powerful military alliance between the southwestern feudal domains of Satsuma and Chōshū formed in 1866 to combine their efforts to restore Imperial rule and overthrow the Tokugawa shogunate of Japan.