Edward Gibbon (1737-1794) did not regret the fall of Constantinople in 1453. He regarded the Byzantine Empire as an unfortunate continuation of the Roman Empire.
He hold Byzantium (and Christianity) responsible for the fall of the Roman Empire and the schism of 1054, dividing and alienating the most useful Christian allies and provoking the Islamic enemies. The accomplishments and millennium of the Byzantine Empire are easily overlooked from this perspective.
The cultural splendours, the relationship between Byzantium and western medieval rulers, the prestige of the Byzantine imperial court, the continuation of the Roman (legal) tradition and the contacts with Islam shaped Europe as it is today. Justinianus was one of the last Byzantine emperors with the title Imperator, two generations later the title was Basileus (Greek for king).
They regarded themselves however as the successors of the Roman emperors and called themselves ‘Rhomaioi’, Greek for Romans. The Byzantine emperor saw himself as the superior Christian ruler.
More than 500 years after the fall of Byzantium, the western part of the Roman Empire still neglects the Byzantine heritage. Founded in 330 by the Roman Emperor Constantine the Great, Constantinople (or Byzantium) became the most powerful cultural, economical and political unified centre in Europe.
The short lived political experiment of Charlemagne and the decentralized Holy Roman Emperors sharply contrasted with the relative success of the Byzantine Empire.
The Greek Orthodox Church and Greek alphabet were introduced in Eastern Europe and Byzantine culture and society were the hall mark for medieval European courts and cities. Though iconoclasm (726-843) destroyed many works of arts, Byzantine artists, courtly mode, style and influence found their way to western Europe. Byzantine art, law, business and administration flourished and pragmatism guaranteed innovative changes and developments. Europe should not be the same without the contributions of this society. The plunder and subsequent occupation by Europeans c.q. crusaders in 1204 is a dark episode.