7 – Durability
Historians generally agree that the Byzantine Empire reached its largest extent in 555 under the rule of Justinian I. From the 7th century onwards, it faced a constant battle to stay together and survived a remarkably long time when you consider the issues it faced. Indeed, Constantinople was considered to be the wealthiest city in Europe until the 13th century. The Byzantines were arguably world leaders in the fields of science, architecture, art and trade.
Even during its Golden Age, the empire was hit with a major crisis in the form of the Plague of Justinian which began in 541 and is believed to have killed almost 25 million people in total. The war with the Sassanid Empire, which began in 602 and lasted for over a quarter of a century, weakened the Byzantines tremendously and made it an easier target for Arab invaders. Large parts of the empire were lost in the 7th century but the Arabs were never able to take Constantinople.
The empire expanded once again during the Macedonian dynasty beginning in the 10th century but was dealt a hammer blow at the Battle of Manzikert in 1071. By now, the Byzantines had lost most of Asia Minor and it appeared as if it would collapse at any time. the Komenian Restoration of the 12th century saw further expansion which came to a grinding halt as Constantinople was successfully sacked for the first time during the Fourth Crusade in 1204.
The Empire of Nicaea managed to reclaim the city in 1261 but it was clear that the empire was in terminal decline. In the middle of the 14th century, a civil war followed by an earthquake at the important fort of Gallipoli devastated the empire. The slow lingering decay and collapse thereafter meant it was at the mercy of the Ottomans who finally took Constantinople in 1453 and ended the Byzantine Empire.
A combination of the other factors mentioned in this article is why the Byzantine Empire was able to continually rebound after disasters. Ultimately, it couldn’t cope over the course of time and like all empires, it was always destined to end. That it lasted over 1,100 years is utterly remarkable and a testament to the ingenuity and determination of the Byzantines.