Chapter 3 examines mythical, historical, and scientific facts. It offers a brief history of East Asian international relations, paying particular attention to the Chinese World Order, the Khmer Empire, and post-colonial Filipino historiography as samples for how to theorize histories from an IR perspective. The chapter discusses war and peace as well as political economy, the subject matters important for East Asian history and IR theory. It also offers a section on impacts and lessons of history, illustrating how history contributes to background knowledge, historiography and belief systems, foreign policy analysis, and IR theory. A better understanding of East Asian history allows us to contextualize contemporary issues without which we may not be able to put together a puzzle. Historical experiences inform our belief system, into which people typically fit new events or factors as explanation. History is evolutionary by nature, whether we frame it that way explicitly or not.

Chapter 3 shows that Linyi kingdom occupied the key relay position in the longest chain of transshipment relays in the world at the turn of the first millennium. It became the most fully Indianised kingdom among all other Southeast Asian countries by the sixth century CE despite its close ties with Chinese courts and markets. Its wide networks built itself a wealthy society along the central coast and its existence proved vital to the prosperity of Jiaozhou under the Chinese rule. The flow of commercial wealth that Linyi generated changed political equations in the Tongking Gulf. Linyi rested on control of two key resources: strategic harbours for ports of call and the aromatic forests of the interior liked by well-established overland trails. These two factors would constitute the economic base of this important polity on the central coast between China and other Southeast Asian neighbours. Linyi did not collapse so much as fade away to re-emerge in part as Champa.

The Vietnamese Le dynasty launched a massive invasion of its neighbor, Champa, in 1471. The invasion, which was the culmination of centuries of back and forth conflict, produced widespread Cham deaths, and the permanent weakening of the southern kingdom. The Vietnamese actions, resulting in at least 40,000 recorded deaths, may well have been genocidal, though the limited historical record is unclear. It does, though, reveal that the Vietnamese used beheading against many of the victims, an action that appears punitive rather than incidental to warfare, and uniquely applied to the Cham. Furthermore, the Vietnamese carried out a project to rename geographical features in the Cham territories, suggesting a degree of cultural erasure while also substantially and permanently reducing the size of the Cham realm. Thus, although the evidence for genocide is ambiguous, it is clear that the Vietnamese actions in the late fifteenth century sought permanently to reduce the influence and threat posed by Champa via an overwhelming show of force.