Originally peasants, primarily Ukrainian and Russian, who fled from bondage to the lower Dnepr and Don river regions to settle in the frontier areas separating fifteenth-century Muscovy , Poland, and the lands occupied by Tatars. The cossacks, engaged in hunting, fishing, and cattle raising, established permanent settlements and later organized themselves into military formations to resist Tatar raids. Renowned as horsemen, they were absorbed into the Russian army as light cavalry or irregular troops by the late eighteenth century.
