Russia today is ruled by the worst and least talented group of villains Russia has seen since before World War II. How did these men come to power? And how did the phenomenon of Putinisma come to pervade the psyche of the nation? In his bold new book, “The Invention of Russia,” Arkady Ostrovsky blames not just systemic pressures from above, but also the cumulative effects of generations of genetic depletion—the survival of the least fit.

Homo soveticus, Mr. Ostrovsky observes, was “a negative selection process that first physically...