Smolensk had been captured by Poland-Lithuania in 1611 during the Polish-Muscovite War of 1609-1619. It had been retained by Poland despite a year long siege during the Smolensk War (1632-34). However, after that war the defences of Smolensk had not been maintained. Of the thirty-two towers built into the town walls, only ten were useable. The garrison in 1654 was only 3,500 strong, and the siege works built in 1632-3 were still present outside the walls.
In 1654 a new war broke out between Poland-Lithuania and Muscovy (Thirteen Years War, 1654-67). Muscovite armies advanced on a wide front. The largest army, 41,000 strong, commanded by Ia. K. Cherkasskii, headed towards Smolensk, with two more armies guarding its flanks. The main Muscovite army reached Smolensk in 2 July and settled back into the old siege works.
The Polish-Lithuanian response was led by Field Hetman Janusz Radziwill, a political enemy of John Casimir. His army was meant to be 11,000 strong, but was probably no more than half that size. He did manage to defeat Cherkasskii at Shklov (12 August 1654) but was then caught and defeated at Shepeleviche (24 August 1654) and forced to retreat back to Minsk.
This left the defenders of Smolensk with no hope of relief. The main Polish army was absent in the Ukraine, attempting to deal with a long standing Cossack revolt and a Muscovite invasion. On 3 October the defenders of Smolensk surrendered. The next year the town would be Tsar Alexis’s base for his invasion of Lithuania. At the end of the war in 1667 Smolensk was retained by Muscovy (Peace of Andrusovo).