various problems and only partly dealt with ethnogenesis. One of the main speakers, historian Abubakir Usmanov, argued that not only Turkic and Finno-Ugric tribes but also the most ancient tribal confederations that inhabited Bash-kiria, and were in the Japhetic stage of development, participated in the for-mation of the Bashkirs.57
In 1950, a conference on Chuvash history and ethnogenesis was held in Moscow. The first speaker, historian and archaeologist Petr Tretiakov, criti-cized the idea that the Chuvash were direct descendants of the Bulghars as a proposition of bourgeois science. He pointed out that not only ancestors of the Chuvash but also those of the Kazan Tatars, the Maris and the Udmurts inhabited Volga Bulgharia. He also claimed that the difference between the northwestern (Upper) Chuvash and the southeastern (Lower) Chuvash had its origin in the second millennium B.C., and that only the latter had a close rela-tionship to strangers-Bulghars. Other speakers also stressed the autochtony of the Chuvash or intercrossing of the aborigines (presumably Finno-Ugric peo-ple) and the Bulghars. Interestingly, while in the case of Tatar ethnogenesis the Bulghars were contrasted to the strangers the Mongols, this time it was the Bulghars who became the strangers. They were referred to as steppe no-mads, although in reality they became mostly sedentary people in the period of formation of the Volga Bulghar state. Some speakers emphasized the influ-ence of the Russians on the Chuvash.58
Soon after this conference, Stalin severely criticized Marrs theory and called him a mere simplifier and vulgarizer of Marxism.59 Officially, the ep-och of Marrist ethnogenetics then ended. Scholars criticized themselves and colleagues for their Marrist past. They denied the Marrist thesis that Ja-phetic languages and ethnoses had been transformed into Indo-European or Turkic ones through jumps (skachoks) and explosions (vzryvs). They also denounced exaggeration of intercrossings effect as well as their underesti-mation of the reverse phenomenon, i.e., branching of one ethnic community into several.60 Elements of Soviet ethnogenetics that derived directly from Marr