A Fateful Morning in Tokyo

On May 14, 1878, just eight months after the conclusion of the Satsuma Rebellion, one of Japan’s most powerful statesmen met a violent end. Ōkubo Toshimichi, Councilor and Home Minister in the Meiji government, was traveling to the Grand Council of State office in Tokyo when six disaffected former samurai from Ishikawa Prefecture ambushed his procession at the base of Kioizaka slope in Kōjimachi. The attackers stabbed and slashed the 47-year-old leader to death in broad daylight, shocking the nation and creating a power vacuum at the highest levels of government.

The assassination represented more than just the death of a prominent official—it symbolized the deep tensions within Japanese society during the rapid modernization of the Meiji period. The assailants, all former samurai , specifically targeted Ōkubo as the embodiment of what they perceived as authoritarian rule by a clique of former feudal domain elites. In their subsequent testimonies, they expressed frustration that Japan’s laws and policies reflected not the emperor’s will nor public deliberation, but rather the arbitrary decisions of a small group of high-ranking officials.

The Architect of Modern Japan

To understand why Ōkubo became a target, we must examine his role in shaping Meiji Japan. Born in Satsuma domain , Ōkubo had been instrumental in the Meiji Restoration that toppled the Tokugawa shogunate in 1868. As one of the most influential leaders in the new government, he championed radical modernization policies that transformed Japan from a feudal society into a modern nation-state.

Ōkubo’s policies often generated controversy. He centralized political power, abolished the feudal domains, implemented land tax reforms, and pushed for rapid industrialization—all measures that disrupted traditional social structures and privileges. His ruthless suppression of samurai rebellions, particularly the Satsuma Rebellion led by his former ally Saigō Takamori, made him many enemies among the warrior class. While his vision propelled Japan toward modernity, his methods earned him accusations of authoritarianism.

The Immediate Aftermath and Succession

The assassination created immediate uncertainty about the future direction of the government. Within hours of the killing, Itō Hirobumi, then 36 years old and serving as Councilor and Minister of Public Works, emerged as the central figure to assume leadership. On May 15, just one day after the assassination, Itō resigned as Minister of Public Works and took over Ōkubo’s position as Home Minister, effectively becoming the leader of the domain-clique government.

Itō’s rapid ascent was not without precedent. He had previously served as acting Home Minister in 1874 when Ōkubo traveled to Beijing to negotiate the settlement of Japan’s expedition to Taiwan. During the Satsuma Rebellion, Itō had worked closely with Ōkubo on personnel and strategic decisions. His position as second only to Ōkubo in the government hierarchy made him the natural successor.

Balancing Domain Politics

Recognizing the need to maintain balance between the powerful Satsuma and Chōshū domains that dominated the government, Itō immediately consulted with Imperial Chancellor Iwakura Tomomi about appointing a Satsuma-born councilor to replace Ōkubo. On May 24, Saigō Tsugumichi was appointed Councilor and Education Minister.

Saigō Tsugumichi’s appointment was strategically significant but politically complicated. As a former army leader who had independently launched the Taiwan Expedition of 1874, he had clashed with Yamagata Aritomo, another powerful leader from Chōshū domain. After receiving Ōkubo’s approval for his actions in Taiwan, Saigō had been effectively demoted to serve as vice president of Japan’s commission to the Philadelphia Centennial Exposition. During the Satsuma Rebellion, he had returned to army service but was subsequently appointed minister to Italy in April 1877, again removing him from military affairs.

Kuroda Kiyotaka, the second most powerful Satsuma leader after Ōkubo, believed Saigō’s promotion was premature. However, Itō and Iwakura proceeded with the appointment, recognizing the need to maintain Satsuma representation at the highest levels. This decision would prove prescient—in December 1885, Saigō Tsugumichi would become Japan’s first Navy Minister, leading the naval forces as a Satsuma elder statesman who cooperated closely with Itō.

The Struggle for Control

The question of who would replace Itō as Minister of Public Works became another point of contention. During this period, ministers simultaneously served as councilors, meaning appointment as Minister of Public Works would grant entry into the cabinet under the Grand Council of State system.

Emperor Meiji twice urged Grand Minister Sanjō Sanetomi to appoint Sasaki Takayuki, his Chamberlain and advisor on imperial virtue from Tosa domain, to the position. After Ōkubo’s assassination, Sasaki and other court officials saw an opportunity to advance their agenda of direct imperial rule, hoping to make the emperor more substantively involved in politics.

Appointing Sasaki would undoubtedly strengthen the imperial rule faction, which is precisely why Itō and Iwakura resisted the appointment. They understood that increasing direct imperial involvement would undermine their ability to implement their modernization agenda.

Building a Power Base

Itō preferred his ally Inoue Kaoru, former Vice Minister of Finance and current Councilor of the Genrōin , for the position of Minister of Public Works. Inoue shared Itō’s commitment to rapid modernization and Westernization.

When word spread about Inoue’s potential appointment, Sasaki and other court officials began obstructing the process. They advised against it to Sanjō and Iwakura and even petitioned the emperor directly. The emperor, already displeased that his suggestion of Sasaki had been ignored by the cabinet, became increasingly resistant to Inoue’s appointment, leaving Itō in a difficult position.

Itō then enlisted the help of Ōkuma Shigenobu, Councilor and Finance Minister, who petitioned the emperor on July 19, 1878, recommending Inoue’s appointment. Itō also sought assistance from Yamagata Aritomo, Councilor and Army Minister, and asked both Sanjō and Iwakura to support the nomination. As a last resort, he considered having Yamagata petition the emperor directly.

The strategy worked. Both Sanjō and Iwakura eventually petitioned the emperor to appoint Inoue, who assumed the position of Councilor and Minister of Public Works on July 29, 1878. In just two and a half months after Ōkubo’s assassination, Itō had successfully countered the imperial rule movement led by the chamberlains and solidified his power base for pursuing modernization.

The Formation of the Itō Leadership System

The political system that emerged after Ōkubo’s assassination centered around Itō Hirobumi and rested on several key pillars. The first was his alliance with Imperial Chancellor Iwakura Tomomi. Their relationship dated back to 1868 when Itō had proposed the radical idea of replacing domains with prefectures , which aligned with Iwakura’s vision. Iwakura had valued Itō’s abilities ever since, reportedly considering him for deputy leadership during the Iwakura Mission of 1871-1873. However, Iwakura, born in 1825, was sixteen years older than Itō and already in declining health by 1878.

The second pillar was Itō’s alliance with his Chōshū compatriots Inoue Kaoru and Yamagata Aritomo. Inoue’s appointment as Councilor and Minister of Public Works proved crucial to establishing Itō’s power base. Approximately a year later, in September 1879, Inoue was promoted to the even more important position of Councilor and Foreign Minister. Meanwhile, Itō maintained direct influence over the Home Ministry while Yamagata controlled the Army, giving the Chōshū faction effective control over domestic administration and security.

Ōkuma Shigenobu, who had helped Itō secure Inoue’s appointment, gradually grew apart from the Chōshū leadership. In October 1881, Ōkuma was expelled from the government during the Political Crisis of 1881 after attacking Kuroda Kiyotaka, the leading Satsuma figure. This incident ironically strengthened Itō’s leadership system by bringing him closer to Saigō Tsugumichi and Matsukata Masayoshi, both Satsuma-born councilors.

Imperial Confidence and Consolidation of Power

Between July and October 1881, Emperor Meiji embarked on an extensive tour of the Tōhoku region and Hokkaido. During this journey, he reportedly criticized several councilors including Kuroda, Saigō Tsugumichi, and Inoue Kaoru, expressing confidence only in Itō among the political leadership. This imperial trust further solidified Itō’s position as the preeminent statesman of Meiji Japan.

By the summer of 1885, when Itō embarked on his mission to study foreign constitutions in preparation for drafting Japan’s own fundamental law, his leadership system was firmly established. The political structure he had built following Ōkubo’s assassination would guide Japan through its critical formative years as a modern nation.

Legacy and Historical Significance

The assassination of Ōkubo Toshimichi and the subsequent rise of Itō Hirobumi marked a critical transition in Meiji politics. While Ōkubo represented the ruthless efficiency sometimes required to transform a feudal society into a modern state, Itō came to embody the more systematic institutional approach that would characterize Japan’s continued development.

Itō’s leadership proved crucial for Japan’s modernization. He would go on to become Japan’s first prime minister in 1885, lead the drafting of the Meiji Constitution, and establish the genrō system that would guide Japanese politics for decades. The political framework he built after Ōkubo’s death provided stability during a period of tremendous social and economic change.

The events of 1878 also demonstrated the ongoing tension between different visions of modernization and governance in Meiji Japan. The conflict between the oligarchic approach favored by Itō and his colleagues and the direct imperial rule advocated by court officials would continue to influence Japanese politics throughout the Meiji period and beyond.

Ultimately, the assassination of Ōkubo and the succession of Itō represented both continuity and change in Japan’s modernization process. While the methods and personnel shifted, the fundamental commitment to building a strong, modern Japan remained unchanged. The political system that emerged from this transition would guide Japan through its rapid industrialization, military expansion, and emergence as a world power—a legacy that continues to shape Japan to this day.