Lev Nikolayevich Gumilyov (Russian: Лев Никола́евич Гумилёв; 1 October 1912, St. Petersburg – 15 June 1992, St. Petersburg), was a Soviet historian, ethnologist, anthropologist and translator from Persian, had a reputation for his highly non-orthodox theories of ethnogenesis.
His parents were two prominent poets Nikolay Gumilyov and Anna Akhmatova. They were divorced when Lev was 7 years old, and his father was executed when Lev was just 9. Lev spent most of his youth, from 1938 until 1956 in Soviet labor camps. He was arrested by NKVD in 1935 and released, but rearrested again and convicted to five years in 1938. After serving the time, he joined the Red Army and took part in the Battle of Berlin. However, he was arrested again in 1949 and convicted to ten years in prison camps. In order to secure his release, Akhmatova published a dithyramb to Joseph Stalin, which did not help to release Lev, although it possibly prevented her own imprisonment. The order for her arrest had already been prepared by Soviet secret police, but Stalin decided not to sign it. Relations between Lev and his mother were strained, as he blamed her for not helping him enough. She described her feelings about the arrest of Lev and the period of political repressions in Requiem.
After Stalin's death, Gumilyov joined the Hermitage Museum, whose director, Mikhail Artamonov, he would come to appreciate as his mentor. Under Artamonov's guidance, he became interested in Khazar studies and steppe peoples in general. In the 1950s and 1960s he participated in several expeditions to the Volga Delta and North Caucasus. He proposed an archeological site for Samandar as well as the theory of the Caspian transgression in collaboration with geologist Alexander Alyoksin as one of the reasons for Khazar decline. In 1960 he started delivering lectures at Leningrad University. Two years later, he defended his doctoral thesis on ancient Turks. From the 1960s, he worked in the Geography Institute, where he would defend another doctoral thesis, this time in geography.