We analyze the history of oil discoveries of different sizes in two centers of the Volga–Ural petroleum province, the Republics of Bashkortostan and Tatarstan, and demonstrate the important role played by Academicians I.M. Gubkin and A.A. Trofimuk in these discoveries. Special focus is placed on the analysis of small and smallest oil fields and the sequence of their discovery. It was shown that all discoveries in Tatarstan and Bashkortostan were the result of the exploration filter. It was also shown that the establishment and support of small oil businesses in Bashkortostan and Tatarstan can be an importance means of the facilitating development of small and smallest fields. The study discusses the role of small independent oil companies in the regional oil production, considers priority areas of state and regional and legal support of small and medium oil enterprises, and presents oil production forecast for Bashkortostan and Tatarstan.