The Principality of Smolensk (eventually Grand Principality of Smolensk) was a Kievan Rus' lordship from the eleventh to the fifteenth century. Until 1127, when it passed to the Rostislavichi, the principality was part of the land of Kiev.

Descendants of Grand Prince Iaroslav I of Kiev (died 1054) ruled the principality until 1125. Following the death of Vladimir Monomakh, Grand Prince of Kievan Rus', Vladimir's son Mstislav I Vladimirovich became the Rus' over-king and Mstislav's own son Rostislav Mstislavich became Prince of Smolensk (ruled 1125-1160). The principality gained its own Orthodox bishopric under the Bishop of Smolensk in 1136.

Rostislav's descendents, the Rostaslavichi, ruled the principality until 1404. Smolensk enjoyed stronger western ties than most Rus' principalities. The principality contained a number of other important cities that usually possessed subordinate status, notable among them Bryansk, Vyazma and Mozhaysk. The principality gradually came under Lithuanian overlordship in the fourteenth-century, being incorporated in the fifteenth. The Grand Duchy of Moscow under Vasili III captured Smolensk in 1514, but lost it again 1611 during the Polish–Muscovite War of 1605–1618 as a result of the Siege of Smolensk (1609–11). The area passed into the Polish-Lithuanian Commonwealth (Rzeczpospolita) as the resurrected Smolensk Voivodeship. In the seventeenth-century the Rus' under Russian control attempted to bring the city into their expanding state again, and despite defeat in the "Smolensk War" (1632–1634) the Tsardom of Russia captured the city in 1654 at a time when the revolt of the Dnieper Cossacks in the Khmelnytsky Uprising (1648-1657) partially distracted the Rzeczpospolita.

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