Boaters, derbies, fedoras—until just a generation or two ago, a man’s social status, if not his very masculinity, was defined by his hat. For centuries, men owned hats for all seasons and occasions. But in the 1960s, the male hat became obsolete. Just as women shed their white gloves for the sexual revolution, men cast aside centuries of tradition and stopped wearing hats.The hat’s demise has over time been credited to President Kennedy, or “Hatless Jack,” due to his reluctance to be photographed wearing a hat for fear it made him look old. But one president alone did not make or break a trend. In this quirky social history, Neil Steinberg traces the evolution of the hat over centuries, as a costly but necessary investment, as a symbol of social status, and masculinity, and as a global industry.