An analysis of Betty Smith’s bestselling coming-of-age novel A Tree Grows in Brooklyn reveals how popular literature can serve as an important introduction to signature issues of the Gilded Age and Progressive Era. Industrialization, urbanization, and immigration are highlighted in the novel—as well as attendant problems including poverty, machine politics, child labor, and prejudice and discrimination. Profound ignorance about sexuality and conception abound in a religious culture that made premarital sex and birth control sinful and shameful, with unhappy marriages and unwanted children the result. As poverty and deviant sexuality abound, eugenics is touted as a sensible solution. The novel helps to explain why there was no organized rebellion or revolution when the struggling poor found that the promise of upward mobility was elusive. Characters have differing definitions of the American Dream. Some seek respite in religion, leisure activities, or alcohol. Others find hope in a variety of reform measures, including public health and education, settlement houses, and unions. The novel ends as the technology that made the nation’s industrialization and urbanization possible continues to produce new marvels that will transform the lives of the urban poor, bringing the Gilded Age and Progressive Era to a close.