This is a map of the Soviet forced labor camp system, the Gulag, which existed between 1923 and 1961. It was created under Lenin and reached its peak during Stalin's rule from the 1930s to the 1950s. The camps housed a wide range of convicts, from petty criminals to political prisoners.

About half of political prisoners in the Gulag camps were imprisoned without trial; official data suggest that there were over 2.6 million sentences of imprisonment on cases investigated by the secret police throughout 1921–53.

Up until World War II, the Gulag system expanded dramatically to create a Soviet "camp economy". Right before the war, forced labor provided 46.5% of the nation's nickel, 76% of its tin, 40% of its cobalt, 40.5% of its chrome-iron ore, 60% of its gold, and 25.3% of its timber.

Prior to the dissolution of the Soviet Union, estimates of Gulag victims cited by Conquest, Solzhenitsyn, and others ranged from 12 to 15 million. Post-1991 research by historians utilizing archival materials brought this range down to 1.6 million. Golfo Alexopoulos, a history professor at the University of South Florida, claims that at least 6 million people died as a result of their detention in the prison camps.

The Gulag institution was officially closed on January 25, 1960, but forced labor colonies for political and criminal prisoners continued to exist. Political prisoners continued to be kept in one of the most famous camps Perm-36 until 1987 when it was closed.

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