Stroganovs' river fleet as a porter and a sailor transporting salt along the Kama and the Volga rivers. Growing tired of his work, he assembled a gang, left his employment, and moved to the Don region to become a river pirate. Among his fellow Cossack bandits, he acquired the nickname Yermak. Prior to his conquest of Siberia, Yermak's combat experience consisted of leading a Cossack detachment for the tsar in the Livonian War of 1558–83 and plundering merchant ships. Based on legends and folk songs, for years, Yermak had been involved in robbing and plundering on the Volga with the hetman Ivan Kolzo and four other Cossack leaders. Historian Valerie Kivelson refers to Yermak's group as “his gang of thugs.” Like many other Cossacks, Yermak's gang was involved in the “thieves” trade (“vorovskim” remeslom). It was typical of Cossacks to engage in piracy on the Sea of Azov or the Caspian Sea and to rob various envoys and Russian or Persian merchants. Though a bandit, Yermak earned a reputation as an eminent and loyal Russian fighter. Through his experience fighting in the Livonian War, he learned war tactics and excelled beyond the other hetmans in skill. Conquest background In the late 1500s, prior to Yermak's expeditions, the Russians attempted to push eastward into Siberia in search of furs. Under Ivan the Great, the Russians entered northwest Siberia but “to approach Siberia from that direction proved too arduous and difficult, even in the best of times.” The Russians decided that taking a southern route through the Tatar khanate of Kazan would allow them to penetrate Siberia more easily, but Kazan would need to be overthrown first. Ivan the Terrible's first foreign objective upon rising to power was to take Kazan. Ivan the Terrible's modernized army proved successful at the beginning of October 1552 and Ivan proceeded to open up the east to enterprising Russian individuals, such as the Stroganovs. Anika Stroganov used the former khanate of Kazan as an entryway into Siberia and established a private empire on the southwest corner of Siberia. Following the Russian conquest under Ivan the Terrible, the Tatar khanate of Kazan became the Russian province of Perm. Ivan the Terrible had tremendous trust in the entrepreneurial prowess of the Stroganov family and granted them the province of Perm as a financial investment which would be sure to benefit Russia in the future. The tsar also gave