In the Soviet Union, the decade of the 1930s saw a remarkable rate of educational expansion, as state schools enrolled millions of pupils in higher proportions and for longer periods of time than ever before. Much of this expansion occurred in the "non-Russian" regions, where the native language of children and thus the primary language of instruction were something other than Russian. So-called "national" schools provided instruction in more than 70 different "native" languages and enrolment exceeded 12 million by the end of the 1930s. Using a variety of published and archival sources, this article argues that Soviet education, like Stalinism more generally, promised to transcend ethnic differences even while perpetuating ethnic distinctiveness. These materials and interpretations suggest new ways of understanding how schools become sites for defining, contesting and negotiating identities. (Contains 64 footnotes.)