At the same time , the tribe of the Pechenegs threatened the Empire in the north , the Normans in the west , the latter being especially dangerous as they had an army and a navy at their disposal . Through their enemy's internal dissensions they had an easy game so that Byzantium lost its possessions in Italy . That the Empire did not collapse is attributable solely to the skill of Alexios I KOMNENOS . Having come to power through a revolt , he was able to stabilise the position with Venetian assistance . In the hope of further assistance from troops , he promoted the idea of crusades , but then had to use his entire diplomatic skill to ensure that Byzantium did not disintegrate under his array of forces .

His successors did not succeed as well with their manoeuvring between the fronts . Manuel I pushed himself into the hazardous project of re-conquering Italy and squandered valuable forces in the process . His pro-Latin ecclesiastical policy alienated him from his subjects . Temporary successes seemed to mark a change in trend , but in reality they accelerated the decline because the funds expended for this overtaxed the economic potentialities . Andronikos , who eliminated Manuel's son , arrested the collapse for a further moment . But his regime ended in 1189 in a reign of terror out of which the dynasty of the Angeloi succeeded to the throne shortly before the first collapse of Constantinople in 1204 . The Byzantines were scattered among various small part empires , their former capital formed the centre of a Latin Crusader state . In Asia Minor , with its centre in Nicaea , Theodore Laskaris was able to consolidate his rule so far that he continued the East Roman tradition .

Once again , the Byzantines' masterly use of tactics triumphed . The Empire was restored from Nicaea and at the same time the last Byzantine dynasty , the Palaiologoi , came to power by a coup . Their age is marked by a cultural flowering completely untroubled by the political and economic decline . From on other period has so much evidence of art and science been preserved . It is impossible to imagine the Italian renaissance without the Greek element .

But the state of Byzantium , which attained European rank again for a last time and just for a few years under Michael VIII , failed to flourish any more . In the 14th. century , the Balkans were lost to the Bulgarians and Serbs , Greece was devastated by the Catalans , Asia Minor conquered by the Ottomans . The inner strength was broken and disintegrated through civil wars , unrest and social tensions . The Empire now consisted only of its capital .

The Church stepped into the state's shoes . Monasteries and clergy gained more and more power ; and after the second fall of Constantinople on 29-5-1453 , they became the bearers of Byzantine culture , of the identity of the Greeks under Turkish-Ottoman rule , of the art of icans and frescoes . In it , Byzantium lives on in a new and revived form .