This paper examines the causal effects of textbook content on individuals’ national identity, by exploiting a curriculum reform that introduced a new perspective on Taiwan’s history for students entering junior high school after September 1997. Using a repeated nationally representative survey and a regression discontinuity design, we show that students exposed to the new textbooks were more likely to hold exclusive Taiwanese identity rather than dual identity (i.e. Taiwanese and Chinese). The effect was greater for academic track students and those living in neighborhoods where fewer people identify as Taiwanese. In addition, our results suggest that the new curriculum had little impact on people’s political preferences related to Taiwan independence. Finally, we find that the probability of reporting as Taiwanese among old textbook readers converges with that of people reading new textbooks in the long run since the perspectives of old textbooks are in conflict with the recent social trends.