The essay reinterprets the 1845–1847 pamphlet war between Emma Willard and Marcius Willson, authors of popular history schoolbooks. Willson publicly attacked the accuracy and literary quality of history schoolbooks by eight leading authors, with particular attention to Willard's, just as he was publishing his first school history. Willard and Willson practiced different kinds of history authorship that reflected their different backgrounds, intellectual milieus, and professional circumstances. This essay questions conventional readings of the debate and argues that their subsequent exchange over plagiarism, style, and sourcing illuminated important issues in the purposes of history education, the challenges of growing markets, and new theories of historiography. The debate showed that schoolbooks were not simply derivative “guardians of tradition,” but that they could be portals for new disciplinary theories in an age without a robust professional research infrastructure to test and filter them.