This article examines a strategy of peace activism that gained visibility in the last decades: memory activism. Memory activists manifest a temporal shift in transnational politics: first the past, then the future. Affiliated with the globally-circulating paradigm of historical justice, memory activist groups assume that a new understanding of the past could lead to a new perception of present problems and project alternative solutions for the future. Based on ethnographic fieldwork and discourse analysis among memory activists of the 1948 war in Israel since 2001, the article examines the activist production of counter-memory during active conflict. Using Coy et al.’s typology of oppositional knowledge-production, the article shows how the largest group of memory activism in Israel produced ‘new’ information on the war, critically assessed the dominant historical narrative, offered an alternative shared narrative, and began to envision practical solutions for Palestinian refugees. However, the analysis raises additional concerns that reach beyond the scope of the typology, primarily regarding the unequal power relations that exist not only between the dominant and activist production of oppositional knowledge, but also among activists.