Migrations are a central issue of the modern period, particularly since World War One. At the same time, the implementation of a systematic policy of categorization, discrimination, persecution, and extermination of European Jews is one of the major events of the first half of the 20th century. How should the relations between these two histories be understood? The goal of this project is to explore the links between migration and the Holocaust from a transnational microhistorical perspective. To this end, it will implement an original method: producing the collective biography of the Jewish inhabitants from the Polish shtetl of Lubartow from the 1920s to the 1950s, whether they emigrated or stayed behind, whether they were exterminated or survived the Holocaust. This research will, for the first time, reconstruct the trajectories of a group of persecution victims across the different places they travelled through, which is possible today thanks to new access to an impressive body of archives and the affordances of the digital humanities. The methodological and archival challenge is immense. This transnational collective biography explores the directions of individual journeys, the diversity of fates, as well as the connections between those who remained and those who left. By doing so, the LUBARTWORLD project addresses some prominent theoretical issues: the dynamics of a social structure drawn into a major disruption, the variability of social categorizations in diverse national and political contexts, and the complex making of identities. From an epistemological point of view, it will develop innovative ways of reconstructing and analyzing life-course information. Although the project begins with Lubartow, it leads to the world in its globality. Lubartow residents crisscrossed the globe, and their trajectories outline and embody in their own way the upheavals of Europe’s relations with the world before, during, and after the Holocaust.