[2] From the 1990s onwards, he has turned to subjects on Russian 20th century history, publishing studies on Lavrentiy Beria, Joseph Stalin, Vyacheslav Molotov and Leonid Brezhnev.
He is one of the Russian historians alongside those who are critically reviewing the part of the Soviet Union in the Second World War.
[3] In 2016, he was expelled from the Free Historical Society for “inappropriate handling of historical sources and incorrect quoting of other people's works.”[4] Sokolov is one of the experts of the film “The Soviet Story”,[5] which caused controversial assessments and accusations of manipulation and falsification[6][7][8] S. Milovanov, in his Ph.D. thesis, counts Sokolov among those who are now resuscitating the “myths of Hitler's propaganda".
[9] Many of Russian historians, sociologists and publicists consider the data on the losses of the Red Army during the Great Patriotic War, given in the publications of B.V. Sokolov, to be unreliable.
Academician of the Russian Academy of Sciences, sociologist Gennady Osipov described B.V. Sokolov as “the most tireless “professional” falsifier,” and called his calculations absurd, since “over all the years of the war, 34.5 million people were mobilized (taking into account the pre-war number of military personnel) , of which about 27 million people were direct participants in the war.