The 23rd workshop on the History and Memory of National Socialist Camps and Extermination Sites took place in Thessaloniki. Before the Second World War Thessaloniki was home to the largest Jewish community in Greece, more than 50.000 Jewish inhabitants in 1941, at the time of the German occupation. In February 1943 German authorities concentrated local Jews in ghettos. Between March and August more than 45.000 of them were deported to Auschwitz-Birkenau, most of whom were gassed on arrival. From the pre-war Jewish community less than 2.000 survived the Holocaust. Despite the significant impact this played in the history of this part of Greece, it was mostly forgotten and hardly represented, both in Greece itself as well as in international studies. The absence of memorialization and the tremendous loss of the Jewish community, as well as the recent interest in commemoration, which serves as affirmation for the identity of the Jewish inhabitants of Thessaloniki, connect the location to the topic of the workshop. The papers published in this volume look at this gap in Holocaust history both with an emphasis on Greece as well as further blanks in current research.