During World War I Berlin physician and psychoanalyst Karl Abraham, one of the members of the Secret Committee centered around Sigismund Freud, after incorporation into the army was transferred from Berlin to provincial Olsztyn, in East Prussia. The preserved correspondence with Freud of this period contains many interesting facts about Abraham’s medical activities in Olszyna during World War I (1915–1918). Garrison psychiatric ward founded here and run by Abraham was one of the few places in Europe, where were the application of psychoanalytic treatment of patients with traumatic neuroses. However, Abraham’s list are also interesting because they contain insights into Olsztyn itself and living conditions in the city during the Great War.