For Americans, HIV/AIDS was a phenomenon of the 1980s. That was when the epidemic first spread across the country; that was when activists galvanized to lobby for changes in the way medical treatments were developed and approved. But as historian Thomas F. McDow describes this month, HIV/AIDS has a much longer history that goes back a century. And while AIDS was initially called "the gay cancer" in the United States, its spread around the world has much more to do with colonialism in Africa and the globalization of the economy in the 20th century.