Later in the ninth century, during the reign of Boris I, the pagan temples in Pliska likely began to be converted to Christian churches. In 886, Boris founded the Pliska Literary School which was moved to Preslav when Boris later relocated the capital. When Boris fell seriously ill and retired to a monastery, his son Vladimir succeeded him and attempted to reestablish paganism. During this period (889-93) the large stone basilica at Pliska built under Boris was heavily damaged. Boris left his monastery to overthrow his son, and after succeeding, relocated the capital to the nearby town of Preslav which seems to have been a centre of Christianity in the state. Following this Pliska's relevance in Bulgar governance steadily declined until the Bulgarian state was destroyed by the Byzantine general turned emperor (when he murdered the previous emperor Nikephoros Phokas) John Tzimiskes. He defeated the Russian forces that had occupied Bulgaria and annexed the Bulgarian lands all the way to the Danube, ending the rule of the first Bulgarian state in these territories. During this Russian and Byzantine war over Bulgaria, Pliska was destroyed between 969 and 972 and was not rebuilt.