By tracing the effects of unprecedented immigration, the advent of the new woman, and the little-known vaudeville careers of performers like the Elinore Sisters, Buster Keaton, and the Marx Brothers, DesRochers examines the relation between comedic vaudeville acts and progressive reformers as they fought over the new definition of "Americanness."

1. Americanization: Progressive Era Reformers, Cultural Critics, and Popular Comic Entertainments 2. Putting It Over in American Vaudeville 3. The New Humor: Ethnic Acts and Family Acts 4. The Marx Brothers Go To School 5. The New Woman and the Female Comedian as Social Insurgent Epilogue