This paper explains election fraud historically in the case of Sweden, drawing on original data from second-instance election petitions filed in 1719–1908. These petitions reveal systematic procedural violations committed by local election officials toward the end of the Age of Liberty in the eighteenth century. By the mid-nineteenth century, however, fraud had been largely purged from Swedish elections, and most petitions instead concerned unclear regulations pertaining to suffrage and eligibility criteria. I argue that this development cannot be explained by changes in electoral rules, the degree of competitiveness, or shifts in economic development or inequality. Instead, the ebb and flow of electoral fraud in Sweden could best be understood as stemming from the professionalization of the bureaucracy in combination with the extent to which elections were partisan. This novel mechanism for generating election fraud is corroborated qualitatively in a within-case longitudinal analysis and from quantitative data on city elections in 1771. I argue that similar processes may explain the rise and fall of election fraud historically in other established Western democracies, such as Britain and the United States.