 In 1635, the Polish Government built the Kodak Fortress above the Dnieper Rapids at "Kodaky" (on the south-eastern outskirts of modern Dnipro), partly as a result of rivalry in the region between Poland, Turkey and Crimean Khanate, and partly to maintain control over Cossack activity (i.e.to suppress the Cossack raiders and to prevent peasants moving out of the area).On the night of ¾ August 1635, the Cossacks of Ivan Sulyma captured the fort by surprise, burning it down and butchering the garrison of about 200 West European mercenaries under Jean Marion.