Vietnam and China first demarcated a border in 1079, when the two sides agreed that “the Quan Nguyen and Guihua prefectures were two sides of a ‘fixed border’ (qiangjie) region between the two states.” When China and Vietnam signed their modern treaty in 1999 they agreed upon essentially this same border. Similarly, the Yalu river, which formed the boundary between Korea and China in 1034 A.D., remains the border today. Ten centuries of the same border is both impressive, and leads us to ask why that was the case.The difference between a border and a frontier is the difference between a line and a space. Borders are fixed—a clear line that separates two different political spaces, with clear rights and responsibilities on both sides of the line. In contrast, a frontier is a zone—an ambiguous area where political control, organization, and institutions gradually diminish and intermingle with other ideas, institutions, rules, and peoples.While some political relationships in early modern East Asia were demarcated by lines, other historical relationships were mediated by space. Those that were demarcated by lines proved to be remarkably stable; those mediated by space proved to be more conflictual.East Asia Before the West focuses on borders and the states that demarcated and controlled them, and on the rules and norms they devised to govern their interactions during a particular time and place in East Asia.A political entity coherent enough to define itself over geography and to negotiate a fixed line and border with another entity requires considerable organization, institutionalization, and a set of ideas. These need to be sufficiently shared with the bordering political entity for the two parties to actually view each other as legitimate, agree on a border, and agree on the rights and responsibilities on both sides. In early modern East Asia, Sinic states had political organization and shared cultural values. China had clear borders with both Vietnam and Korea, which combined for long periods of stability.How much of the past affects the present in East Asia?The East Asian tribute system dissolved quickly in the nineteenth century when the arrival of the West and its norms, institutions, and ideas, created an enormous challenge to the existing worldviews of East Asian nations. The tribute system is gone, never to return. It is thus unlikely that patterns of behavior that existed under the tribute system would continue under these Western ideas in the current international system.On the other hand, Western ideas and institutions have not ever been universally accepted—and even within the West there have been numerous exceptions to and selective acceptance of the ostensibly universal principles. Thus, it might be worth exploring how much and how deeply East Asian states have internalized these Western notions—and whether and to what extent any of East Asia’s past history may affect their beliefs and goals in the future.The difference between China at the height of its hegemony five centuries ago and China today is most clearly reflected in the fact that few people today think that China is still the cultural center of the world. Few contemporary East Asian states or peoples look to China for cultural innovation or for practical solutions to present-day problems.The question is not only whether China reaches back to its past for guidance—the questions are also whether other states and peoples will believe contemporary China’s goals and intentions are benign, and whether contemporary China finds a stable identity for itself within the Westphalian system.