This biographical note on historian Aleksei Petrovich Smirnov (1899-1974) provides relevant statements on the frames and limitations of scientific activity under Soviet rule before and after WWII. A Marxist archaeologist and a believer, Smirnov survived these tragic times and managed to publish reference books under pressure from party organs. After studies in archaeology at the MGU with V. A. Gorodtsov and Iu. V. Got’e, Smirnov began in 1924 to conduct his own expeditions in Udmurtia for his dissertation on the “Kama Finnish in the Tenth to Fourteenth Centuries.” Graduated in 1929, he began to distance himself from his old professors. After Got’e’s arrest, Smirnov criticised Gorodtsov’s methodology in an article published in 1932. A member of the Society of Marxist Historians led by M. N. Pokrovskii, Smirnov successfully applied the ethno-genesis theory of N. Ia. Marr on the history of Tatars and Chuvashs, focusing his scientific interest on the archaeology of Volga Bulgharia. On the basis of excavations at Suvar (1933) and Bulghar (1938), he published in 1940 his work “Essay on the History of Ancient Bulghars [Ocherki po istorii drevnikh Bulgar].” After WWII, as the vice-director of the Institute of Archaeology of the Academy of Sciences of the USSR, he led two major expeditions that enriched the history of the non-Russian peoples of the Volga region. He published his famous book on the Volga Bulghars in 1951 and after Khrushchev’s accession to supreme power, he criticised these “archaeological studies which after 1946 presented the Golden Horde only negatively.” Spending most of his time on the field, he was ill when he transmitted in 1969 the direction of his archaeological expeditions to his student G. A. Fedorov-Davydov. Finally, the biographical account of this well known Soviet scholar demonstrates the high level of scientific activities in the post-WWII Soviet Union. Written in 1956 by Smirnov to one of his student from Kazan, the two letters published as appendixes to the article evoke the virulent debates provoked by his theory on the Finno-Ugric origin of the Chuvashs.