Rus ' – Byzantine War ( 860 ) The Rus ' – Byzantine War of 860 was the only major military expedition of the Rus ' Khaganate recorded in Byzantine and Western Europe an sources . Accounts vary regarding the events that took place , with discrepancies between contemporary and later sources , and the exact outcome is unknown . It is known from Byzantine sources that the Rus ' caught Constantinople unprepared , while the empire was preoccupied by the ongoing Byzantine - Arab Wars and unable to deal with the Rus ' threat . After pillaging the suburbs of the Byzantine capital , the Rus ' retreated , although the nature of this withdrawal , and indeed which side was victorious , is subject to debate . This event gave rise to a later Orthodox Christian tradition , which ascribed the deliverance of Constantinople to a miraculous intervention by the Theotokos . Background . It is not clear when the Rus ' and Byzantines first came into contact . The first mention of the Rus ' near the Byzantine Empire comes from " Life of St . George of Amastris " , a hagiographic work whose dating is debated . The Byzantines had first come into contact with the Rus ' in 839 . The exceptional timing of the attack suggests the Rus ' had been informed of the city ' s weakness , demonstrating that the lines of trade and communication did not cease to exist in the 840s and 850s . Nevertheless , the threat from the Rus ' in 860 came as a surprise ; it was as sudden and unexpected " as a swarm of wasps " , as Photius put it . The empire was struggling to repel the Arab advance in Asia Minor . In March 860 , the garrison of the key fortress Lulon unexpectedly surrendered to the Arabs . In April or May , both sides exchanged captives , and the hostilities briefly ceased ; however , in the beginning of June , Emperor Michael III left Constantinople for Asia Minor to invade the Abbasid Caliphate . Raid . On June 18 , 860 , at sunset , a fleet of about 200 Rus ' vessels sailed into the Bosporus and started pillaging the suburbs of Constantinople ( Old East Slavic : " Tsarigrad " , Old Norse : " Miklagarðr " ) . The attackers were setting homes on fire and drowning and stabbing the residents . Unable to do anything to repel the invaders , Patriarch Photius urged his flock to implore the Theotokos to save the city . Having devastated the suburbs , the Rus ' passed into the Sea of Marmora and fell upon the Isles of the Princes , where the former Patriarch Ignatius of Constantinople was in exile at the time . The Rus ' plundered the dwellings and the monasteries , slaughtering the captives . They took twenty - two of the patriarch ' s servants aboard ship and cut them into pieces by axes . The attack took the Greeks by surprise , " like a thunderbolt from heaven " , as it was put by Patriarch Photius in his famous oration written on the occasion . Emperor Michael III was absent from the city , as was his navy dreaded for its skill in using lethal Greek fire . The Imperial army ( including those troops that were normally garrisoned closest to the capital ) was fighting the Arabs in Asia Minor . The city ' s land defences were weakened by the absence of these garrisons , but the sea defences were also lacking . The Byzantine Navy was occupied fighting both Arabs and Normans in the Aegean Sea and the Mediterranean Sea . These simultaneous advantages left the coasts and islands of the Black Sea , the Bosporus , and the Sea of Marmara susceptible to attack . The invasion continued until August 4 , when , in another of his sermons , Photius thanked heaven for miraculously relieving the city from such a dire threat . The writings of Photius provide the earliest example of the name " Rus " ( " Rhos " , ) being mentioned in a Greek source ; previously the dwellers of the lands to the north of the Black Sea were referred to archaically as " Tauroscythians " . The learned patriarch reports that they have no supreme ruler and abide in some distant northern lands . Photius called them " έθνος άγνωστον " , " unknown people " , although some historians prefer to translate the phrase as " obscure people " , pointing out to the earlier contacts between Byzantines and the Rus ' . Later traditions . The sermons of Photius offer no clue as to the outcome of the invasion or the reasons why the Rus ' withdrew to their own country . Later sources attribute their retreat to the Emperor ' s speedy return to the capital . As the story goes , after Michael and Photius put the veil of the Theotokos into the sea , there arose a tempest which dispersed the boats of the barbarians . In later centuries , it was said that the Emperor hurried to the church at Blachernae and had the robe of the Theotokos carried in procession along the Theodosian Walls . This precious Byzantine relic was dipped symbolically into the sea and a great wind immediately arose and wrecked the Rus ' ships . The pious legend was recorded by George Hamartolus , whose manuscript was an important source for the Primary Chronicle . The authors of the Kievan chronicle appended the names of Askold and Dir to the account as they believed that these two Varangians had presided over Kiev in 866 . It was to this year that ( through some quirk in chronology ) they attributed the first Rus ' expedition against the Byzantine capital . Nestor ' s account of the first encounter between the Rus ' and the Byzantines may have contributed to the popularity of the Theotokos in Russia . The miraculous saving of Constantinople from the barbarian hordes would appear in Russian icon - painting , without understanding that the hordes in question may have issued from Kiev . Furthermore , when the Blachernitissa was brought to Moscow in the 17th century , it was said that it was this icon that had saved Tsargrad from the troops of the " Scythian khagan " , after Michael III had prayed before it to the Theotokos . Nobody noticed that the story had obvious parallels with the sequence of events described by Nestor . In the 9th century , a legend sprang up to the effect that an ancient column at the Forum of Taurus had an inscription predicting that Constantinople would be conquered by the Rus . This legend , well known in Byzantine literature , was revived by the Slavophile s in the 19th century , when Russia was on the point of wresting the city from the Ottomans . Criticism . As was demonstrated by Oleg Tvorogov and Constantine Zuckerman , among others , the 9th century and later sources are out of tune with the earliest records of the event . In his August sermon , Photius mentions neither Michael III ' s return to the capital nor the miracle with the veil ( of which the author purportedly was a participant ) . On the other hand , Pope Nicholas I , in a letter sent to Michael III on September 28 , 865 , mentions that the suburbia of the imperial capital were recently raided by the pagans who were allowed to retreat without any punishment . The " Venetian Chronicle " of John the Deacon reports that the " Normanorum gentes " , having devastated the " suburbanum " of Constantinople , returned to their own lands in triumph ( " et sic praedicta gens cum triumpho ad propriam regressa est " ) . It appears that the victory of Michael III over the Rus ' was invented by the Byzantine historians in the mid - 9th century or later and became generally accepted in the Slavic chronicles influenced by them . However , the memory of the successful campaign was transmitted orally among the Kievans and may have dictated Nestor ' s account of Oleg ' s 907 campaign , which is not recorded in Byzantine sources at all .