# Curzon Ultimatum

The Curzon Ultimatum was a British ultimatum delivered by British Foreign Secretary Lord Curzon to the Soviet government on the 8 May 1923. The ultimatum was a response to heightened Soviet revolutionary agitation in Islamic Asia and India, areas under British influence or control. The Ultimatum called for the Soviet Union to completely cease its revolutionary agitation and operations in Afghanistan, Persia (Iran) and India, including the withdrawal of Comintern envoys in those regions. The ultimatum threatened to cut diplomatic and strategic trade ties with the Soviet Union if it refused.
On 4 June 1923, the Soviet Union agreed to these demands, not willing to sever newly built economic ties with the United Kingdom that were necessary to their industrial development. The negotiations were hailed as a success by both Lord Curzon and the Soviet Government, as Britain was able to ward off Communist revolutionary activity, whilst the Soviet Union maintained their trade relations.

## Background
### British–Soviet relations after the Russian Revolution

British intervention in Russia was a crucial aspect of early Soviet-British relations, reflecting the broader geopolitical tensions of the period. As historian Sergeev states, "It was Britain’s contribution to this controversial process that I meticulously explore bearing in mind its regional variations and interconnection with the policies of other contemporary geopolitical actors." Britain played a significant role in the anti-Bolshevik intervention, which was not uniform but varied by region and was influenced by the actions of other major powers.
British military and financial support for White Russian forces underscored its initial hostility toward the Soviet regime, contributing to the strained relations that persisted in the early years of Soviet statehood.
Western scholars largely viewed Bolshevism as a threat that needed containment, though they differed on the motivations behind British intervention in Russia. Some believed Britain sought to prevent a Bolshevik defeat, while others argued the goal was to curb American influence in Eastern Europe. Some framed the intervention as a moral effort to counter totalitarianism, while others saw the Russian Civil War as a continuation of World War I, highlighting British military intelligence’s role in shaping Allied operations.
By 1922, the Comintern had built a considerable network of pro-Soviet spies, agitators, and revolutionary leaders in Afghanistan, Persia, and India. These forces often mobilized with nationalist, anti-colonialist movements that pushed back against British political and military dominance.
Between 1918 and 1924, British-Soviet relations evolved significantly within the broader context of the post-World War I Versailles international order. The formation of the Versailles international order had an impact on both the spirit and dynamics of bilateral contacts in all spheres. This can be seen with regard to the initial hostility, reflected in the Entente’s intervention against the Soviet regime, which changed “first to humanitarian, then to economic and finally to political collaboration, culminating in the USSR’s diplomatic recognition by the UK.” This shift illustrates the gradual transformation of British policy toward the Soviet Union, moving from direct military intervention to pragmatic engagement.

### Soviet involvement in Islamic and South Asia

The Bolshevik Revolution and the subsequent establishment of the Third International played a pivotal role in promoting global revolution and fostering anti-colonial and anti-imperial agitation across Europe and Asia. By advocating for the spread of communist ideology, the Comintern sought to unite revolutionary movements worldwide, challenging colonial rule and imperial dominance. This internationalist approach was also integral to sustaining the Russian Revolution, as the Soviet leadership viewed the exportation of revolution as essential to securing and legitimizing their socialist experiment.

### British intelligence on Soviet activities in Asia and the build-up to the ultimatum

British intelligence played a crucial role in gathering evidence to support the claims made in the Curzon Ultimatum, particularly regarding Soviet support for anti-British movements in India and Afghanistan. The British government viewed Soviet interference in these regions as a direct threat to its imperial stability and sought concrete proof of such activities. Intelligence agencies intercepted Soviet diplomatic communications, which provided evidence of Soviet involvement in revolutionary agitation, including support for Indian nationalist movements and subversive activities in Afghanistan. These findings reinforced British suspicions and justified the firm stance taken in the ultimatum, highlighting the broader geopolitical struggle between Britain and the Soviet Union in the early 1920s.
Of all the intelligence received at the Foreign Office, news of revolutionary activity directed at India and the North-West Frontier Province “disturbed Curzon most”. When the Lloyd George government fell in November 1922, and a Conservative Cabinet was installed with Andrew Bonar Law as prime minister, Curzon was able to operate with less constraint than before. Thereafter, in the absence of the détente-oriented Lloyd George, Curzon's own intransigent policy toward Russia played an increasingly significant role in British foreign relations. His aim in 1922-23 was to sever the relations with Russia into which Lloyd George had led the government. His policy found ready support from John D. Gregory, head of the Northern Division at the Foreign Office and its expert on Russian affairs, who weighed the tactical considerations. Gregory calculated that a break in relations with Russia was a weapon that could be used only once, and then only "if and when there is a reasonable chance of upsetting the Soviet government or at least dealing an effective blow to its stability."
The British Foreign Office relied extensively on decoded Soviet diplomatic correspondence to substantiate its claims against the Soviet Union. This intelligence was provided by the Government Code and Cipher School (GC & CS), which played a critical role in intercepting and deciphering Soviet communications$^3$. The information obtained through these efforts reinforced British allegations of Soviet support for anti-British revolutionary movements in India and Afghanistan, thereby strengthening the justification for the Curzon Ultimatum.

## The ultimatum and its demands

On 8 May 1923, British Foreign Secretary Lord Curzon delivered the ultimatum to Maxim Litvinov, marking a significant moment in British-Soviet relations. The Curzon Ultimatum was a direct response to Soviet revolutionary activities in Asia, particularly in Persia (Iran), Afghanistan, and India, which were perceived as threats to British imperial interests.
The British government accused the Soviet Union of actively supporting anti-British revolutionary movements, including the infiltration of Indian revolutionaries who had received training in Tashkent and Moscow. Additionally, the Curzon Ultimatum placed particular emphasis on the British demand that the Soviet Union cease its support for anti-British revolutionary movements in Asia. The British government accused the Soviets of actively aiding and training Indian revolutionaries in Tashkent and Moscow, as well as fomenting unrest in Persia (Iran) and Afghanistan. In response, the ultimatum demanded an immediate halt to these activities, alongside a formal apology and the recall of Soviet representatives involved in such actions. Failure to comply would result in severe repercussions, including the termination of the Anglo-Soviet Trade Agreement and the withdrawal of British diplomatic representatives from Moscow.
These demands reflected Britain's broader concerns over Soviet interference in its imperial territories and highlighted the fragile nature of Anglo-Soviet relations. By leveraging the threat of economic and diplomatic isolation, Britain sought to curb Soviet revolutionary influence while reaffirming its geopolitical dominance in the region. This ultimatum underscored Britain's determination to safeguard its imperial interests by curbing Soviet influence in its colonial territories and maintaining geopolitical stability in the region.

### Soviet response

The Soviet response to Lord Curzon’s demands varied. Georgy Chicherin, Commissar of Foreign Affairs and the chair of the NKID (People’s Commissariat for Foreign Affairs), objected to the demand of recalling representatives in Afghanistan and Persia, while Maxim Litvinov was offended by the ultimatum. Soviet diplomats, including Leonid Krasin, successfully negotiated an extension of the ultimatum’s deadline to 4 June 1923. The Soviet government remained largely conciliatory, agreeing to some of the demands in order to avoid the breakdown of Anglo-Soviet relations, whilst denying other accusations altogether.

## Outcome and aftermath
### Soviet compliance with British demand

The crisis reached its resolution when the Soviet Union conceded to British demands through diplomatic notes sent on 4 June and 9 June 1923. In these communications, the Soviet government agreed to halt its support for revolutionary activities in Asia, aligning with Britain's insistence on limiting Soviet influence in the region. Furthermore, Moscow accepted an expanded definition of "propaganda" as outlined by the British, effectively curbing its ideological outreach. This strategic concession demonstrated the Soviet Union's willingness to prioritize diplomatic stability over ideological expansion, at least temporarily.

### Aftermath

Lord Curzon hailed the resolution of the crisis as a significant British triumph, declaring a "considerable victory" over the Soviet government. This sentiment was echoed by Prime Minister Stanley Baldwin and widely endorsed by the London press. However, the Soviet Union also perceived the outcome as a diplomatic success. By engaging in skillful and measured negotiations, the Soviet People’s Commissariat for Foreign Affairs (NKID) managed to avoid a complete rupture in relations with Britain. Most importantly, the Soviet government preserved the Anglo-Soviet Trade Agreement, ensuring continued economic ties despite the political tensions. As historian Geoffrey Roberts notes, "Curzon claimed what he called ‘a considerable victory over the Soviet government’; Stanley Baldwin, who was appointed prime minister during the crisis, agreed, and so did the London press. But the outcome was a success for Russia too. The NKID’s skillful, cautious, and conciliatory diplomacy thwarted the primary intention of Curzon and the Foreign Office, either to break off relations or to inflict a humiliating defeat on Soviet policy in Asia."
Although the Curzon Ultimatum crisis was resolved diplomatically, it left a lasting impact on Anglo-Soviet relations. While Britain celebrated what it saw as a diplomatic victory, suspicions regarding Soviet activities in Asia persisted, preventing a deeper rapprochement between the two nations. Meanwhile, the Soviet Union remained wary of British intentions, viewing the ultimatum as an attempt to assert dominance rather than a genuine effort to improve relations. Despite these tensions, the Anglo-Soviet Trade Agreement remained intact, allowing for continued economic engagement.

## Long-term impact

The Curzon Ultimatum of 1923 sharply demonstrated the geopolitical split between Britain and the Soviet Union, deeply rooted in Moscow’s support for anti-colonial movements in Asia which challenged British imperial dominance. Soviet foreign policies, aimed at provoking revolutionary dissent through the Comintern in regions like Islamic Asia, agitated intense British backlash. At the centre of this confrontation was the role of intelligence, as British agencies carefully documented Soviet insurrection, contributing the evidentiary foundation for diplomatic refusals.
The signing and acceptance of the Ultimatum serves to highlight the seemingly contradictory stances of early Soviet foreign diplomacy. One one hand, Lenin’s Comintern, and the basis for this theory of global revolution relied on internationalizing the Bolshevik revolution, especially into colonial territories. On the other hand, the NKID had simultaneously promoted “peaceful coexistence” and even cooperation with Imperialist nations in order to obtain the necessary trade of technological material for future industrialization.
The Soviet signing of the ultimatum and the ultimate withdrawal of Comintern forces from Islamic and South Asia underpinned that the economic and security interests of the Soviet Union lied ahead of continued revolutionary agitation. The Soviet Union continued to engage in short-term loan borrowing and specific trading relations with the United Kingdom, but due to internal British debate on whether or not to recognize the legitimacy of the new Bolshevik government, formal, long lasting relationships were not established until the Soviet Union’s official acceptance and entry into the League of Nations in 1934.