Recent scholarship on collective memory and nationalism in Latin America argues that – in sharp contrast to Europe – war commemoration has been of little importance to the memory work of states in the region. The article challenges this claim. A comparative-historical analysis of school textbooks and school ceremonies in twentieth-century Mexico, Argentina and Peru reveals that the commemoration of major civil and international wars was central to official national narratives in these countries. The article further identifies important qualitative changes in war commemoration over time, especially with respect to how commemorative discourses portrayed agency and assigned responsibility for military victories and losses. These changes are situated within broader transformations of nationalism and new alignments in the politics of nationhood and memory.