The breakdown of the monopoly of coinage in Spanish America by the 1820s meant the cessation of the silver standard that had fueled the expansion of global trade in the early modern period. This article analyzes the resulting economic effects in China and the United States. The analysis connects monetary developments in Spanish America with demand-side explanations within China and the increasingly dominant role of North Americans as intermediaries of the world's silver trade after the 1780s. The article challenges established notions that silver outfl ow from opium imports or silver shortages from falling South American output were the main causes of economic troubles in nineteenth-century China. Through a comparison with the workings of North American institutions in managing domestic monetary effects, the article highlights the puzzling lack of any monopolistic monetary authority in imperial China.