Cossacks were military groups which first emerged during the 15th - 16th century, consisting of impoverished nobles and peasants who had fled serfdom. Theories about their origins vary greatly. The cossacks sometimes lent their military strenght to protectorates, and in the second half of the 16th century, they also executed Ivan the Terrible's conquest of Siberia. Their leader Yermak conquered the Khanate of Sibir and thus became a driving force of the Russian invasion and conquest of Siberia. The sculpture shows a symbolic battle scene of the cossacks who were especially proficient in fighting on horseback.