Flappers took over during the 1920s; they were trendy women with bob haircuts and slender, lean builds. Showing their disdain for what was considered polite and acceptable feminine behavior, flappers smoked, drank, danced, drove cars, listened to jazz, and reveled in casual sex.
During this time, men weren’t immune to the pressures of body image, either. Because women were beginning to behave more like men, living life vivaciously and sometimes recklessly, gender roles were already changing. By now, women could vote, drive cars, choose who they married, and even hold jobs that were previously allotted only to men. As a result, men began clinging to attributes that defined their masculinity — like mustaches — a trend that would continue well into the next several decades.