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Ushkuyniks (Russian: ушкуйники), also ushkuiniks were medieval Novgorodian pirates which operated along the Volga River, the eastern part of Scandinavia, and north of the Ural mountains in 12th-15th century. Some historians see them as a continuation of Viking traditions of ancient Rus' people.
Novgorodians took part in the Tsargrad expeditions of the 10th century and other raids on Byzantine Empire, mounted pillaging raids to Finland since 12th century (see Swedish–Novgorodian Wars),including seizing its capital - Turku.
Ushkuyniks first appear in the historical record as an organized force in the 1320s. Arranged in squadrons which could number several thousand, Ushkuyniks enjoyed the patronage of influential boyar families of Novgorod, who used them to demonstrate Novgorod's military clout to its neighbours and to advance its trade interests and influence along the Volga river.
During the campaign of 1360, ushkuyniks sailed from Novgorod by the portages to the Volga river. Under command of boyar Anfal Nikitin, they gained possession of Zhukotin, a trade emporium in Volga Bulgaria. A ruler of the Golden Horde, which controlled Zhukotin, was furious and ordered Grand Prince Dmitry Konstantinovich to capture the ushkuyniks and to bring them to the Horde for trial, but Dmitry's punitive expedition failed.
Three years later, without consulting their superiors in Novgorod, they approached Nizhny Novgorod and, wishing to punish Dmitry for his hostile action, massacred Armenian and Tatar merchants trading there. This led to a diplomatic row, when Dmitry demanded apologies from Novgorod Republic.
In 1371 Ushkuyniks sacked Yaroslavl, Kostroma and other Upper Volga cities. Three years later they sailed with upwards of ninety ships to pillage the Vyatka region. In 1375, they defeated the militia of Kostroma and burnt the city to the ground. The destruction was so severe that Kostroma had to be rebuilt elsewhere. After that, they looted Nizhny Novgorod and sailed down the Volga to Astrakhan, where they were annihilated by a Tatar general.
By 1391 Ushkuyniks had recovered from this reverse and felt strong enough to resume their activities. At that period their patrons included Narimantas and Patrikas, the overlords of the Korela district that later became known as Ingria. In 1391 the pirates sacked both Zhukotin and Kazan. With Muscovy's power on the ascendant, however, Novgorod Republic was pressed into putting down their filibustering activities in the first decades of the 15th century.
Vernadsky, Viktor Nikolayevich (1961). Новгород и новгородская земля в XV веке (Novgorod and the Novgorod Land in the 15th Century). Leningrad (Saint Petersburg): published by the USSR Academy of Sciences. pp. 36–51.