Cyrus McCormick invented the revolutionary mechanical reaper in 1831...right? At least, that's how the story has been told for decades. In Harvesting History: McCormick's Reaper, Heritage Branding, and Historical Forgery (U Nebraska Press, 2023), National Park Service historian Daniel Ott argues that not only have textbooks and other sources of historical knowledge gotten this wrong, but that they've done so because of a massive PR campaign. Ott argues that McCormick, his family, and the company that bears his name, all engaged in a multi-decade long fight to convince potential buyers that their reaper was the first, and given the potentially millions of dollars at stake in a competitive farm implement marketplace, claiming so was no exercise in arcane trivia. In the late 19th and early 20th century. McCormick's company recruited salesmen, advertisers, and newly professionalized historians to shape a narrative about the reaper that sanded over the complex and contingent nature of its invention, and turned McCormick into an American hero. The history told by these groups was malleable enough to fit changing times, as populists and progressives came and went - the claim of "first" gave McCormick's reaper credibility its competitiors could never match. Harvesting History is a story about the importance of getting the story right, and why some people will go to great lengths to make sure we keep getting the story wrong.