Memories of war, terrorism, and natural disaster play a critical role in the construction of group identity and the persistence of group conflict. Here, we argue that personal memory and knowledge of the collective past become entwined only when public events have a direct, forceful, and prolonged impact on a population. Support for this position comes from a cross-national study in which participants thought aloud as they dated mundane autobiographical events. We found that Bosnians often mentioned their civil war and that Izmit Turks made frequent reference to the 1999 earthquake in their country. In contrast, public events were rarely mentioned by Serbs, Montenegrins, Ankara Turks, Canadians, Danes, or Israelis. Surprisingly, historical references were absent from (post-September 11) protocols collected in New York City and elsewhere in the United States. Taken together, these findings indicate that it is personal significance, not historical importance, that determines whether public events play a role in organizing autobiographical memory.