‘‘‘Who am I?’ and ‘Who are we?’ are the existential, foundational questions in our lives. In our modern world, there is no construct more influential than ‘identity’ – whether as individuals or as groups. The concept of group identity is the focal point of a research group named “A Question of Identity” at the Mandel Scholion Interdisciplinary Research Center in the Humanities at the Hebrew University of Jerusalem. The papers collected in this volume represent the proceedings of a January 2017 conference organized by the research group which dealt with identity formation in six contextual settings: Ethno-religious identities in light of the archaeological record; Second Temple period textual records on Diaspora Judaism; Jews and Christians in Sasanian Persia; minorities in the Persian achaemenid period; Inter-ethnic dialogue in pre-1948 Palestine; and redefinitions of Christian Identity in the Early Modern period.