On the evidence of language, the Finnic stock is divided into four branches, The Chudic, The Bulgaric, The permic, The Ugric.
"Lectures on The Science of Language"
Max Müller
The permic tribes were driven westward by their eastern neighbors, the Voguls, and thus pressed upon their western neighbors, the Bulgars of the Volga.
"Lectures on The Science of Language"
Max Müller