This chapter recounts China’s participation at the First Hague Conference of 1899, where the Qing Empire was a formally included but in practice highly marginalized participant, and the implications of the so-called Boxer Rebellion that also erupted in 1899, and was followed by the subsequent Eight Nation collective occupation that radically escalated nineteenth-century practices of intervention. The use of international law as a mechanism for systematically coordinating the interests of expanding Western commercial empires in non-Western spaces was now accorded quasiconstitutional status by the new treaty arrangements reconstructing the nearly collapsed Qing political authority.