This is a lecture sponsored by Humanities Texas and published online in July 2016. David Oshinsky’s lecture was funded by the Pulitzer Prize Centennial Campfires Initiative in observance of the one-hundred-year anniversary of the Pulitzer Prize. The lecture was delivered as part of Humanities Texas's 2016 "Post-War America, 1945–1960" teacher institute in Austin. Who could have imagined that Ron Chernow's fine biography of Alexander Hamilton would inspire a blockbuster Broadway musical? We are always surprised when historians have a genuine impact beyond academic and general readers of history. Yet, at least three of David Oshinsky's writings have had such an effect on society. First came his fine book Worse than Slavery: Parchman Farm and the Ordeal of Jim Crow Justice, which received the Robert F. Kennedy Book Award for Justice and Human Rights. In awarding the prize, the center’s judges stated that "this impressive work reminds us that the abolition of slavery did not end the institutionalized oppression of African Americans." Worse than Slavery was published in 1997, long before the issue of mass incarceration became part of the public dialogue. Then there was an influential article that David wrote for the New York Times after an eerie encounter with the notorious Mississippi preacher and Ku Klux Klan leader Edgar Ray Killen. David's New York Times story, more than thirty years after the murder of the three civil rights workers in the summer of 1964, helped focus national attention on this monumental miscarriage of justice. The preacher was subsequently indicted, convicted, and imprisoned. Finally, there is David’s Pulitzer Prize-winning book Polio: An American Story. It has had a dramatic effect on the drive to eliminate polio worldwide through the leadership of the Gates Foundation. As Bill Gates has explained, "Reading Oshinsky's book broadened my appreciation of the challenges associated with global health issues and influenced the decision that Melinda and I made to make polio eradication the top priority of the foundation, as well as my personal priority." What greater impact can a historian have than that? M. L. G. David Oshinsky, professor of history at New York University and director of the Division of Medical Humanities at NYU Medical School, delivers a lecture on polio at Humanities Texas's "Post-War America, 1945–1960" teacher institute in Austin.