In cultural terms, as compared to many other Russian groups, the South Russian (Kursk) settlers of Siberia in the late 19th to early 20th centuries were a distinct group, having their own traditional culture but usually no compact settlements. In this work, for the first time, on the basis of the State Archive of the Kursk Region, the ethno-cultural composition of Siberian settlers from that region is examined. Attitudes of South Russian peasants of the post-Reform era to migration are analyzed, reasons underlying their “wanderlust” and their reflection about relocation and ethnic identity are explored. Documents at the State Archive of the Tomsk Region, and the findings of my fi eld studies in 2014– 2018 pertaining to the Siberian stage in the history of Russian “Yuzhaks” (Southerners) suggest that their priority was to live side by side with Ukrainian settlers, as they had used to do in their homeland. The reason is that the key role in the early 20th century migrations was played by Russian-Ukrainian frontiersmen—people of “no man’s land”. At the time of migration to Siberia, those living in the southern Kursk Governorate were Russian Old Believers, Southern Russians, Belarusians, Ukrainians (Little Russians), Russian Cossacks, and “Cherkassians” (Ukrainian Cossacks). The latter preferred to live apart from others, even within a single village. Archival documents and findings of field studies in the Anzhero-Sudzhensky District of the Kemerovo Region, and in the Topchikhinsky and Kulundinsky Districts of the Altai Territory demonstrate that Southern Russians were situationally identical to Ukrainians, as evidenced, for instance, by the frequent shift of surname endings from “-ko” and “-k” to “-ov” and vice versa, depending on migration plans. A conclusion is made that the ethnic diversity of migrants from the Kursk Governorate, the situational equivalence of Eastern Slavic groups in Siberia, as well as marriages with Russian old residents and Ukrainians, were key factors in the formation of local Siberian variants of the South Russian culture.