In November 1663 Jan II Casimir and Hetman of Right-bank Ukraine, Pavlo Teteria, began an offensive against Left-bank Ukraine with an army of 130,000 (including camp followers). Without sufficient forces to stop the offensive, Grigory Romodanovsky and Ivan Briukhovetsky retreated to Putyvl. Proceeding almost without resistance, the army of Jan II Casimir ultimately besieged Hlukhiv, which was defended by the Cossacks of the Kievan polkovnik Vasily Dvoretsky and the Russian streltsy of Avraam Lopukhin.