By the eve of the First World War, the world’s two most powerful imperial powers, Britain and France, had begun to work together in order to defeat the growing menace posed by transnational anti-colonial networks operating within Europe. When it came to the front lines of the anti-colonial struggle, however, Franco-British collaborative policing efforts continued to be plagued by persistent rivalries and contestations between these erstwhile enemies. This is particularly evident in the case of the French-controlled settlement of Chandernagore in India, which was one of the centres of revolutionary activity in Bengal. This article examines how Chandernagore’s unique legal and political status as a French possession enabled it to become a ‘haven’ or ‘Alsatia’ for Indian revolutionaries operating against the British colonial state. It traces how the persistence of this vestige of French sovereignty placed it at the centre of repeated conflicts between British and French colonial authorities over the detection, arrest, and extradition of these revolutionaries, revealing both the possibilities and limitations of colonial police cooperation. Far from being peripheral in nature, these conflicts cut to the heart of even more fiercely contested debates within the imperial metropole about the relationship between national sovereignty and international law in an increasingly global age
