This article argues that early modern European assessments of Chinese astronomy and, accordingly, antiquity were largely shaped by local concerns about conflicting schemes of political order. Exploring a little-studied controversy between the Anglican vicar and orientalist George Costard and the French Jesuit in Beijing Antoine Gaubil, the article examines the political stakes involved in promoting or rejecting Chinese astronomical chronology in Georgian Britain and Qing China, respectively. For Whig Anglicans, accepting Chinese astronomical chronology risked legitimizing the "despotic" political system that produced it. Conversely, for Jesuits in China, overtly rejecting Chinese astronomy and antiquity imperiled missionaries' lives and the very survival of the mission. Eighteenth-century European political discourses thus both shaped and were subtly shaped by debates about Chinese astronomical practices and their relationship to antiquity.