People are routinely involved in remembering the national past and imagining the national future, especially when making political decisions. These processes, however, have not been explored extensively. The present research aims to address this lacuna. In 2 experiments (N = 203), participants were asked to remember and imagine events that involve the United States. Later, they rated these events in terms of phenomenal characteristics, valence, and perceived agency (circumstance, self, other-people, nation). Their responses were also coded for specificity and content. Past and future responses correlated for specificity, phenomenology, valence, and the four domains of perceived agency. Despite this strong correspondence between past and future thinking, there were also differences. Future responses were less specific and more positive than past responses. Moreover, people thought that they themselves and their nation will have more control over their nation's future compared with the control they attributed to themselves and their nation over its past. The bias to be more optimistic about the nation's future was partly explained by this tendency to see the nation as more agentic in the future. Taken together, these results reveal striking similarities and divergences between autobiographical and collective mental time travel. The present research provides an exploration for the newly emerging field of collective mental time travel.