After being reduced to about 1,200 animals in eight isolated populations by the beginning of the 20th century, European beavers (Castor fiber) have powerfully recovered in both range and population, through relaxation of persecution, natural spread, and widespread reintroductions. Populations are now (2003) established in all countries within their former natural range in Europe except for Britain, Portugal, Italy, and the south Balkans (Greece, Albania, Bulgaria, Macedonia; status in Bosnia-Herzegovina is uncertain). In Asia, there are significant populations in central Siberia, Kamchatka, and on the Amur; and small relict populations elsewhere in Siberia, and in Xinjiang (China)/western Mongolia. The current minimum population estimate is 639,000. Both populations and range are in rapid expansion. We present maps summarizing current knowledge of the world distribution of European beaver and the Eurasian distribution of the introduced American beaver (Castor canadensis), and tables of the most recent known population estimates for each country.