Lev Nikolayevich Gumilev (1912–1992) was a Soviet and Russian researcher, archaeologist, geographer, historian, and ethnologist, known as the author of the theory of ethnogenesis. Within this concept, the origin and evolution of an ethnos are viewed as the result of the combined influence of many factors—historical, natural-geographical, climatic, and others—while the key principle is “the unity of blood and soil.” In his works, Gumilev traced how the Russian ethnos formed over centuries, what traits shaped the Russian nation, and how Russian statehood developed. He noted: “We don’t want to acknowledge that the foundation of ethnic relations lies beyond the sphere of consciousness—because it is in emotions: sympathies and antipathies, love and hate. And the direction of these sympathies and antipathies is quite determined for each ethnos.” The edition is provided in A4 PDF format, preserving the book’s original layout.