Аннотация:This article examines trajectories of nationalism in twentieth-century Argentina, Mexico, and Peru through the analytical lens of schooling. I argue that textbooks reveal state-sponsored conceptions of nationhood. In turn, the outlooks and practices of teachers provide a window for understanding how state ideologies were received, translated, and reworked within society. During the late nineteenth century, textbooks in Mexico, Argentina, and Peru conceived of the nation as a political community, emphasized civilization for having achieved national unity, and viewed elites as driving national history. During the twentieth century, textbooks eventually advanced a cultural understanding of the nation, envisioned national unity to be achieved through assimilation into a homogeneous national identity, and assigned historical agency to the masses. Yet teacher responses to the textbooks varied. In Mexico, under Lázaro Cárdenas (1934–1940), teachers predominantly embraced textbooks that promoted a popular national culture. Teachers in Argentina under Juan Perón (1946–1955) and in Peru under Juan Velasco (1968–1975) largely opposed the texts.