At the outset of the twenty-first century, the world is facing a range of problems, including environmental, economic, and security risks, that increasingly challenge the logic of nation-state governance. While American and European models of International Relations and global governance, such as the Westphalian system of states and the Washington Consensus, have come under attack from poststructuralist thinkers, political philosophers from China and Taiwan have tried to reconceptualise the world of the twenty-first century from their own perspectives. This article examines current streams of Chinese International Relations theorising and confronts them with the case of territorial disputes in the East China Sea. The article analyses the arguments by Chinese realists, ‘worldists’, and procedural constructivists, showing how Chinese scholars creatively revive pre-modern Chinese political theory in attempts to provide new ways in which International Relations scholars might view the world, or: ‘all-under-heaven’. I argue that these contributions will progressively challenge conventional theories of International Relations, while at the same time contending that so-called non-Western theorising, if it is to contribute to IRT, will require additional rigorous empirical grounding, a critical perspective on its entanglement with nationalist political discourses in East Asian societies, and the willingness to incorporate existing theories.