In Spring of 1656 Swedish garrisons stayed in 31 Polish cities. They numbered about 34.000 men, while a field army was around 15.300 men (9.600 of foot, 5.000 of cavalry & 300 dragoons)
Swedish garrisons in Poland, Spring 1656

Source: Gennari C.A. Invasion, Insurgency & Interventions: Sweden's wars in Poland, Prussia & Denmark 1656-1658. 2010.
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