Title

Results of recent genetic studies of Slavic-speaking populations correlate well with held beliefs about the Slavic spread, suggesting a combination of 1) migrations of Slavs into new territories and 2) language shift among autochthonous populations. Here I compare genes and languages across the three traditional Slavic sub-groupings: West, South, and East Slavic. Male genetic markers (Y-chromosomes) divide Slavic-speaking populations into distinct northern vs. southern groups (Rębała 2007). Bulgaria, Macedonia, Bosnia, Serbia, and northern Croatia form the southern group, which genetically patterns more with Southern European populations than with other Slavs and linguistically belongs to the greater Balkan Sprachbund. West and East Slavic Y-chromosomes pattern with one another more than with neighboring non-Slavic, e.g., German, populations (Ploski 2002, Rębała 2007). However, northwestern Russian populations have a much higher frequency of Y-chromosomes that match neighboring Finnic and Baltic populations (Malyarchuk 2004). This corresponds to the known language shift from Finnic (and Baltic) to Slavic in these areas, evidenced in particular by substratal features in northwestern Russian. Interestingly, maternal lineages (mitochondrial DNA/mtDNA) reveal different patterns. In both East and West Slavic, mtDNA differences are gradual precisely where Y-chromosomes show marked differentiations (Malyarchuk 2004). This suggests that Slavs migrated throughout the central latitudes of Slavic-speaking areas, Slavic males mixing with local populations. But in the south and far northeast, Slavic spread more through language shift than through population movements. Genes are a powerful tool for delimiting the extent of prehistoric language shift, revealing a greater than supposed degree of shift in southern and northeastern Slavdom.