Résumé : The data was collected in 2020, in the context of a doctoral thesis in social and cultural psychology at the University of Brussels, Belgium. Thesis title: Were we all victims and perpetrators? How national and religious identifications and processes of victimhood and responsibility attributions for the civil war affect present-day intergroup relations in Lebanon. This thesis aims to study the role of ingroup identification in shaping construals of group victimhood and responsibility attributions, in addition to the impact of these factors on intergroup relations. We choose to study this phenomenon in the context of the Lebanese civil war, in Lebanese citizens currently residing in Lebanon, evaluating two types of ingroup identification (national and religious) in the two main religious groups (Christians and Muslims). Quantitative data collected via online survey among Lebanese citizens currently residing in Lebanon. This project aimed to assess the effect of manipulating competitive and inclusive victimhood, in addition to ingroup identification, on intergroup relations in Lebanon and other factors (Outgroup attitudes, willingness to engage in contact, intergroup similarity perception, forgiveness, collective action and responsibility attribution). Method of data collection (sample description, procedure, variables scales and items), and a codebook (variables names and their code explained, to better understand the csv and sav data files) are provided. CMLCW P4: Collective Memory of The Lebanese Civil War (project acronym) Project #4 (the thesis included 5 projects/Datasets).