By analysing a Tay chronicle and Chinese sources about a case of usurpation in the Tay (Shan) polity of Mäng: Wan: located in southwest Yunnan on the border with Burma (Myanmar) in 1573, this article offers an alternative approach to the use of chronicles as sources for the history of the Tay Cultural Area. It argues that Tay chronicles are media for the creation and transmission of historical memories, and that they can be utilized to redress the excessive subjectivity of Chinese sources precisely because they show how the Tay interpreted events. Analyses of these interpretations in turn reveal the principal concepts underlying Tay political and social organization, thereby allowing historians to establish benchmarks for ascertaining the changes that took place in Tay polities. This study emphasizes that the memory of the usurpation was generated by the realities of Mäng: Wan:'s power relations with China and Burma, and demonstrates that apart from elucidating the role of royal succession, these memories also throw light on some of the larger recurring themes in the history of Tay relations with China, such as the role of Han Chinese migrants in polity building and administration and land alienation by contractual transactions.