Introduction: Japan at a Diplomatic Crossroads

In the closing decades of the 19th century, Japan found itself navigating the complex waters of international diplomacy while simultaneously building a modern state. The Meiji Restoration had set the nation on a transformative path, but unequal treaties imposed by Western powers during the preceding decades continued to constrain Japanese sovereignty. These agreements, particularly those governing extraterritoriality and tariff autonomy, became symbols of Japan’s subordinate international status and targets for revision by successive governments. Against this backdrop, Foreign Minister Aoki Shūzō embarked on what would become one of the most contentious diplomatic initiatives of the era—a treaty revision negotiation with Britain that would ultimately cost him his political standing and reshape Japan’s approach to foreign relations.

The Historical Context of Treaty Revision Efforts

Japan’s journey toward treaty revision began almost immediately after the Meiji Restoration in 1868. The unequal treaties signed with Western powers in the 1850s and 1860s had granted foreign nationals extraterritorial rights—exempting them from Japanese jurisdiction—and denied Japan control over its own tariff policies. These provisions were not merely symbolic affronts to national pride; they had tangible economic and political consequences that hindered Japan’s development as a modern state.

Previous attempts at treaty revision had ended in failure or controversy. The most notable prior effort, led by Foreign Minister Ōkuma Shigenobu in 1889, had collapsed amid political scandal and public outrage over perceived concessions to foreign powers. When Aoki Shūzō assumed the foreign ministry portfolio in the first Yamagata Aritomo cabinet, he inherited both the institutional memory of these failed attempts and the pressing need to address what remained Japan’s most significant diplomatic challenge.

Aoki brought to the position considerable international experience, having served as Japan’s minister to Germany and developed a sophisticated understanding of European power dynamics. His approach, outlined in what became known as the “Aoki Memorandum,” represented a pragmatic attempt to balance Japan’s desire for full sovereignty with the political realities of international negotiation.

The Yamagata Cabinet and Initial Negotiations

The first Yamagata cabinet took office in December 1889, with treaty revision standing prominently among its priorities. Prime Minister Yamagata Aritomo, primarily concerned with domestic stability and military modernization, granted Aoki considerable latitude in pursuing negotiations with Britain, then Japan’s most important treaty partner.

In September 1890, the British government presented its initial proposal for treaty revision. Aoki, recognizing the need for broad political support, secured the appointment of Interior Minister Saigō Tsugumichi and Communications Minister Gotō Shōjirō as full plenipotentiaries for the treaty negotiations. This move effectively sidelined former foreign ministers Itō Hirobumi and Inoue Kaoru, who had previously led revision efforts but whose involvement might have complicated the political dynamics.

When the British proposal came before the cabinet in October 1890, it faced significant opposition. Many ministers objected to specific provisions, particularly those related to the timeline for ending extraterritoriality and the limitations on tariff autonomy. The cabinet ultimately voted to reject the proposal as a basis for negotiation, sending Aoki back to the bargaining table.

Aoki’s Revised Proposal and British Counterdemands

By March 1891, Aoki had developed a revised negotiation position that attempted to address both British concerns and Japanese priorities. His proposal contained several key elements: abolition of extraterritoriality with a six-year transition period ; increased tariff rates from 0.5% to an average of 1.1% ad valorem; removal of the condition that new treaties would only take effect one year after implementation of Japan’s new legal codes; and issuance of twelve-month travel visas for British nationals to visit Japan’s interior before extraterritoriality ended.

The British response, delivered by Minister Hugh Fraser on March 24, requested several modifications: inclusion of “certain permanently valid provisions” and reinstatement of the condition regarding implementation of Japan’s new legal codes. Fraser’s counterproposal would have restored Japanese jurisdiction over foreign nationals but potentially indefinitely limited tariff autonomy. Given that Japan had not yet implemented its civil and commercial codes, acceptance could have delayed treaty implementation indefinitely if legal reforms stalled.

The Geopolitical Context of British Concessions

Britain’s willingness to negotiate meaningful concessions on extraterritoriality reflected strategic calculations extending beyond bilateral relations with Japan. Two factors particularly influenced British policy: concern that Germany might develop its own approach to treaty revision and potentially gain influence at Britain’s expense; and recognition that Japan’s establishment of a parliamentary system created political constraints that made unilateral abrogation of existing treaties increasingly likely.

British commercial interests also played a significant role. Japan represented an important market and trading partner, particularly as industrialization accelerated in both nations. Fraser’s insistence on maintaining limitations on tariff autonomy reflected Britain’s desire to protect its commercial advantages while conceding on jurisdictional matters that had become increasingly difficult to justify as Japan modernized its legal system.

Growing Domestic Opposition and Political Maneuvering

Despite these strategic considerations, Aoki’s negotiation approach faced mounting criticism within Japanese political circles. In early May 1891, Inoue Kaoru—Itō Hirobumi’s close ally and former foreign minister—wrote to Itō arguing that Aoki’s negotiations should be suspended. Inoue expressed particular concern about Aoki’s independent negotiating style, noting that the foreign minister had engaged in discussions with Fraser before securing formal cabinet approval on April 4.

Inoue shared these concerns with other prominent figures from the Chōshū domain, including Justice Minister Yamada Akiyoshi, Minister to France Nomura Yasushi, and Finance Minister Matsukata Masayoshi. This coordinated opposition reflected both substantive disagreements with Aoki’s approach and the complex factional politics that characterized Meiji governance.

Agriculture and Commerce Minister Mutsu Munemitsu, along with influential bureaucrats Inoue Kowashi and Itō Miyoji, kept Itō and Inoue informed about developments in the negotiations. Their reports heightened concerns about Fraser’s demand for “permanently valid provisions,” which Aoki seemed potentially willing to accept despite the long-term constraints such provisions would impose on Japanese sovereignty.

The Changing Political Landscape

Prime Minister Yamagata had decided to resign following the conclusion of the first Diet session, having achieved his primary objective of establishing stable parliamentary governance. His relatively brief tenure of approximately fifteen months had solidified his position as the second-most influential figure in the Meiji oligarchy, behind only Itō Hirobumi.

Both Yamagata and Emperor Meiji hoped Itō would succeed as prime minister, but Itō declined—not from lack of interest in governing, but from strategic calculation. Having previously criticized Ōkuma’s treaty revision efforts and contributed to the downfall of the Kuroda cabinet, Itō wished to avoid further confrontation with the Satsuma faction and preferred that a Satsuma figure lead the next government.

On May 6, 1891, Matsukata Masayoshi of Satsuma assumed the premiership, forming the first Matsukata cabinet. All Yamagata cabinet ministers initially retained their positions, including Aoki as foreign minister. However, Matsukata’s relatively weak position within the oligarchy—he lacked the influence of Itō, Yamagata, or Kuroda—raised questions about his ability to provide strong leadership, particularly on contentious issues like treaty revision.

The Ōtsu Incident and Its Political Consequences

The political situation changed dramatically on May 11, 1891, when Tsuda Sanzō, a police officer assigned to protect Russian Crown Prince Nicholas during his visit to Japan, attacked the prince with his sword in Ōtsu. The assault, which left Nicholas wounded though not fatally, triggered immediate concern about potential Russian retaliation.

Since the 1880s, Japanese leaders had feared Russian expansionism, particularly through Korea. The Ōtsu incident transformed what had been a celebratory visit into a diplomatic crisis that threatened to provide pretext for Russian aggression. From Emperor Meiji to ordinary citizens, the nation worried about possible war with a far more powerful military opponent.

The government’s rapid and effective response to the crisis—including Nicholas’s medical treatment, appropriate punishment of the attacker, and diplomatic outreach to Russia—ultimately prevented escalation. However, the incident distracted political attention from treaty revision and highlighted the vulnerabilities that made diplomatic equality with Western powers so urgent.

The Collapse of Aoki’s Position

The Ōtsu incident occurred at precisely the wrong moment for Aoki’s treaty negotiations. As the government focused on managing the crisis with Russia, support for his diplomatic initiative eroded further. Political opponents, including Itō and Inoue, used the distraction to intensify their criticism of his negotiation approach.

By late May, Aoki found himself increasingly isolated within the cabinet and the broader political establishment. His independent negotiating style, which had initially been tolerated as potentially effective, now appeared reckless in the context of heightened international tensions. The combination of substantive concerns about his concessions to Britain and factional politics ultimately proved insurmountable.

Matsukata, facing his own political challenges as a relatively weak prime minister, proved unable or unwilling to defend his foreign minister. Without strong backing from the premiership, Aoki’s position became untenable. His treaty revision effort, which had come closer to success than any previous attempt, collapsed amid the political turmoil following the Ōtsu incident.

Cultural and Social Impacts

The treaty revision debates reflected broader social and cultural transformations underway in Meiji Japan. The passionate public interest in diplomatic affairs demonstrated growing national consciousness and engagement with international matters. Newspapers provided extensive coverage of both the treaty negotiations and the Ōtsu incident, helping to shape public opinion and creating pressure on political leaders.

The contrast between the celebratory reception for Nicholas before the attack and the panic that followed highlighted Japan’s complex relationship with the West—simultaneously emulative and resentful, welcoming and fearful. This ambivalence would characterize Japanese foreign relations for decades to come.

Legal reforms undertaken in preparation for treaty revision, including development of modern civil and commercial codes, accelerated Japan’s transformation into a modern legal state. Although these reforms were initially driven by diplomatic necessity, they ultimately contributed significantly to Japan’s internal development and modernization.

Legacy and Historical Significance

Aoki’s failed treaty revision effort represented both progress and setback in Japan’s quest for diplomatic equality. His negotiations achieved greater British flexibility on extraterritoriality than previous attempts, establishing important precedents that would facilitate eventual success in 1894. However, his political failure demonstrated the difficulties of balancing international negotiation with domestic politics.

The episode highlighted the growing influence of public opinion and parliamentary politics on foreign policy. No longer could treaty revision be conducted entirely behind closed doors by a small group of oligarchs. The establishment of the Diet created new political dynamics that future negotiators would need to navigate.

Aoki’s downfall also illustrated the persistent tension between pragmatism and principle in diplomacy. His willingness to consider compromises that might have achieved partial revision contrasted with the uncompromising stance of political opponents who preferred no agreement to one that fell short of full equality. This tension would recur in Japanese diplomacy throughout the modern period.

Finally, the conjunction of the treaty revision effort with the Ōtsu incident underscored the interconnectedness of domestic and international affairs in Meiji Japan. Diplomatic initiatives could be derailed by unexpected events, and foreign policy needed to account for both international power dynamics and domestic political realities.

Conclusion: Lessons from a Diplomatic Near-Miss

Aoki Shūzō’s treaty revision effort stands as a significant chapter in Japan’s emergence as a modern nation-state. His negotiations brought Japan closer to ending the unequal treaties than any previous attempt, yet his political failure demonstrated the complex challenges of conducting diplomacy in a rapidly changing political environment.

The episode reveals much about Meiji Japan’s political dynamics—the factional rivalries, the growing influence of public opinion, the tension between pragmatism and principle. It also illustrates the broader international context in which Japan operated, particularly the strategic calculations of Western powers and the global power dynamics that shaped bilateral relations.

Although Aoki’s specific approach failed, his negotiations established important groundwork for the successful treaty revision that would follow under Mutsu Munemitsu in 1894. His effort represented a necessary step in Japan’s journey toward diplomatic equality and full sovereignty—a journey that would ultimately transform Japan from subject of unequal treaties to imperial power in its own right within little more than a decade.

The story of Aoki’s rise and fall thus offers not merely historical interest but enduring insights into the challenges of navigating between international aspirations and domestic constraints, between pragmatic compromise and principled stand—dilemmas that continue to resonate in international relations today.