The work of the famous Russian historian Pyotr Vasilyevich Golubovsky, offered to the reader, is one of the most thorough studies on the history of the Smolensk land until the beginning of the 15th century. By the time this work was written, two important administrative regions of ancient Russia, Smolensk and Polotsk, remained unexplored in Russian historiography. The author undertook to show in as much detail as possible, on the basis of all known sources, the process of formation and development of one of the most powerful principalities, as well as the further transition of the Smolensk region under the rule of Lithuania. An innovative feature of P.V. Golubovsky's research is the involvement of archaeological material and its comparison with written sources, which until the beginning of the 20th century remained a rare exception to the general rule of alienation of most professors of Russian history from the achievements of archeology.