Eurasia: North, Baltic, White, Barents, Black and Caspian Sea basins; Aegean Sea basin only in Maritza drainage; eastward to Kolyma drainage (Siberia); westward to Rhine and eastern drainages of England. Absent from North Sea basin in Sweden and Norway. In Baltic basin north to about 66°N. Widely introduced to Italy, England and France but possibly often confused with Carassius gibelio (Ref. 59043). At least one country reports adverse ecological impact after introduction.