Around April 21–22, 1648, word of an uprising had spread through the Commonwealth. Either because they underestimated the size of the uprising, or because they wanted to act quickly to prevent it from spreading, the Commonwealth's Grand Crown Hetman Mikołaj Potocki and Field Crown Hetman Marcin Kalinowski sent a vanguard of 3,000 soldiers under the command of Potocki's son, Stefan (in fact, commanded by Commissioner Szemberg and Lieutenant Czarniecki) deep into Cossack territory, without waiting to gather additional forces from Prince Jeremi Wiśniowiecki. Stefan's force consisted of 7 banners of dragoons (700-800 men), 11 banners of cossack style cavalry (550 men) and 1 banner of Winged Hussars (150 men), the rest of his force was composed of about 1,500 registered Cossacks. While this group travelled by land, an additional detachment was sent down the Dnieper river in boats to join Stefan Potocki's forces in due course. These troops, under the command of Polkovnyk (colonel) Mykhailo Krychevsky, Stanislaw Wadowski, Stanislaw Gorski, Illiash Karaimovych and Ivan Barabash, were composed almost entirely of registered Cossacks (they also included about 80 of German dragoon) and numbered at around 3,500.