to be burnt by the Patriarch of Constantinople, Leo Styppes, in May 1140, on the grounds that they incorporated elements of Bogomil belief and practices. One of the few members of the imperial family to be placed in an important position by John was his cousin, Adrian Komnenos (son of John's uncle the sebastokrator Isaac). Adrian had become a monk, adopting the monastic name John, and had accompanied the emperor on his campaigns of 1138. Soon afterwards, Adrian was appointed Archbishop of Bulgaria as John IV of Ohrid. Bulgaria was an autocephalous see and required a prestigious man as archbishop. Military exploits Though he fought a number of notable pitched battles, the military strategy of John II relied on taking and holding fortified settlements in order to construct defensible frontiers. John personally conducted approximately twenty five sieges during his reign. The Pechenegs destroyed (1122) In 1119–1121 John defeated the Seljuq Turks, establishing his control over southwestern Anatolia. However, immediately afterwards, in 1122, John quickly transferred his troops to Europe to counter a Pecheneg invasion across the Danube frontier into Paristrion. These invaders had been auxiliaries of the Prince of Kiev. John surrounded the Pechenegs as they burst into Thrace, tricked them into believing that he would grant them a favourable treaty, and then launched a devastating surprise attack upon their fortified camp. The ensuing Battle of Beroia was hard-fought, John was wounded in the leg by an arrow, but by the end of the day the Byzantine army had won a crushing victory. The decisive moment of the battle was when John led the Varangian Guard, largely composed of Englishmen, to assault defensive Pecheneg wagon laager, employing their famous axes to hack their way in. The battle put an effective end to the Pechenegs as an independent people; many of the captives taken in the conflict were settled as soldier-farmers within the Byzantine frontier. Conflict with Venice (1124–1126) After his accession, John II had refused to confirm his father's 1082 treaty with the Republic of Venice, which had given the Italian republic unique and generous trading rights within the Byzantine Empire. Yet the change in policy was not motivated by financial concerns. An incident involving the abuse of a member of the imperial family by Venetians led to a dangerous conflict, especially as Byzantium had depended on Venice for its naval strength. After a Byzantine retaliatory attack on Kerkyra, John