after that, the fur trade between the great perm and western europe was possible only via the novgorod republic, which became the suzerain of all northern russia. after the centralization of russian principalities by the grand dukes of moscow, the princes of perm, who already had russian names, became their vassals as well as answering to novgorod. great perm–cherdyn supplied a great deal of silver paid as tribute of moscow, which in turn paid the golden horde. tension between moscow and novgorod led to a war of 1471, after which the defeated novgorod republic was annexed by the grand duchy of moscow. the next year (1472) cherdyn, pokcha, and all other towns of great perm also became the prizes of conquest. the main fort of the muscovites was built in pokcha, located to the north of cherdyn. it was burned by indigenous tribes in the beginning of the 16th century.