This thesis argl:les that the foreign interventions in the Taiping civil war were a key turning point in. nineteenth century Sino-foreign relations. The interventions shaped foreign ideas about the application of international law to China. When the prospect of intervention was raised foreign observers and foreign officials discussed how such involvement was justified under 'the law of nations'. The direct collaboration between the Qing and foreign states in suppressing the Taiping, however, led to a change in foreign perceptions about China's place in the state system. Noting what they perceived to be deficiencies in Qing statecraft, foreign observers began to suggest that Qing China was outside of the international system comprised of 'civilised' states. As a result, they suggested that international law was not applicable in China. This revises our understanding of the development of international law in the nineteenth century by suggesting that it was structured as much at sites of empire by foreign officials and communities as it was in the work of European . jurists. Secondly, the thesis takes the Taiping interventions as a case study for exploring the 'negotiation of sovereignty' in China. Sovereignty in China was fractured by the foreign right to extraterritoriality, or exemption from Qing law. The various foreign interventions against the Taiping, including the interventions of British and French state armies and foreign mercenaries, as well as foreign projects to transfer technology to China, raised questions about the extent of foreign sovereignty within the Qing empire. For example, were foreign mercenaries in the service of the Qing still foreign subjects and hence exempt from Qing law? In order for the Qing and foreign agents and states to collaborate in suppressing the Taiping the limits of foreign sovereignty had to be negotiated and these disputes had to be resolved.