As a result of economic and demographic development of Mogilev (Mohylew in Polish sources) during 16th-17th centuries it had become an important trade city of Grand Duchy of Lithuania (GDL).
presented himself as a defender of Orthodox faith, which was met with sympathy of a significant part of the population of Mogilev, especially of commoners (czerń).
[4] Around Christmas time of 1654 a counter-offensive of the Lithuanian army headed by Janusz Radziwiłł and Wincenty Korwin Gosiewski, started.
Pokłoński allegedly promised Radziwiłł to switch sides, and indeed, on February 15 Pokłoński with 400 men of szlachta and his "cossacks" did this, and with his help the Lithuanian forces managed to take over the suburbs,[1] the area inside the so-called Circular Rampart (Круговой вал, Circular Wall), the "New Town" ( Новый город) fortification, however the city proper stood, despite the fact that a considerable number of dwellers were unhappy with Russian rule, sympathized Radziwiłł, and moved away with Lithuanian forces when they were fended off the inner Lesser Rampart.
[1] As of 2003[update] little primary sources exist about the period 1655–1660, i.e., until the next siege of Mogulev [ru] in this war.