“Dirtier than the dogs of Constantinople.” “Waves of human scum thrown upon our beaches by other countries.” Such was the vitriolic abuse directed against immigrant groups in Chile and Argentina early in the twentieth century. Yet only twenty-five years earlier, immigrants had encountered a warm welcome. This dramatic change in attitudes during the quarter century preceding World War I is the subject of Carl Solberg’s study. He examines in detail the responses of native-born writers and politicians to immigration, pointing out both the similarities and the significant differences between the situations in Argentina and Chile. As attitudes toward immigration became increasingly nationalistic, the European was no longer pictured as a thrifty, industrious farmer or as an intellectual of superior taste and learning. Instead, the newcomer commonly was regarded as a subversive element, out to destroy traditional creole social and cultural values. Cultural phenomena as diverse as the emergence of the tango and the supposed corruption of the Spanish language were attributed to the demoralizing effects of immigration. Drawing his material primarily from writers of the pre–World War I period, Solberg documents the rise of certain forms of nationalism in Argentina and Chile by examining the contemporary press, journals, literature, and drama. The conclusions that emerge from this study also have obvious application to the situation in other countries struggling with the problems of assimilating minority groups.