Rome is captured by the Ostrogoths and subsequently, the Western Roman Empire falls. The Eastern Roman Empire (Byzantium) is left as the last bastion of Roman civilisation. Byzantium inherits all of Romes technology, society. culture, religion and military achievements.
Justinian marries Theodora who will become his empress and help him maintain order at home as he reconquers lost Roman territory.
Justinian I reigns as emperor of Byzantium. As one of the greatest emperors, Justinian will bring the empire to its territorial zenith by reconquering much of the lost Western Roman Empire. He also codified the law and constructed the Hagia Sophia.
Justinian I builds the church of Hagia Sophia in Constantinople. It will remain an icon to the paramount status of religion in Byzantine society for a thousand years.
The second, and most important of Justinian's reformations and collections of Roman law into a single reliable source. These laws will provide the legal basis for all of Byzantium, lending great stability to the society.
A continuation of the near millennia long conflict between Persia and the Romans. Although the Byzantines are technically victorious, the result of this war will leave both empires drastically weakened and unable to defend themselves from the holy warriors of Islam.
Under Justinian I the empire reaches its territorial height, having reclaimed Italy and North Africa from the barbarians.
With most Latin speaking territories lost and the Greek lands being the core of the empire Heraclius sets Greek as the Official language of Byzantium.
Heraclius overthrew the Justinian dynasty in 610 and upon coronation officially changed the language of the empire from Latin to Greek. He furthermore, defeated the Sassanids in the final Perso-Roman War and founded the “Theme System” which would provide a strong, loyal military to the Byzantine empire for another 600 years.
The holy city of the Christians and Jews falls to the Persians and 65,000 Christians are massacred. The "true cross" is stolen from its shrine which prompts Heraclius to lead his forces deep into Persia to retrieve the holy artifact.
Muslim Arabs begin their massive invasion into Byzantine lands seizing Syria, North Africa and the Levant. Eventually reaching the gates of Constantinople they are only turned back by the mysterious power of Greek Fire.
A period of massive internal strife and upheaval in which there was essentially no stable government. The only reason the Empire survived this period was a remarkably strong military and the Arabs failure to take advantage of the Byzantine's weak situation.
Leo III's reign is marked by the brief return to stability and the repulsion of most invaders from Byzantine lands. After repelling the invaders, Leo attempted to retake land from the Muslims but these campaigns ended in defeat. It was these defeats that led Leo to launch the Iconoclast.
The Iconoclasts was a period of time in which the Byzantine Church was dysfunctional as the unpopular iconoclasm of Leo III had divided the Empire upon the topic of religious Icons.
Michael III's regent, his mother Theodora, brought about the end of Iconoclast disasters by declaring Icons legal and supported by the imperial throne. When Michael ascended to the throne and began to expand the empire, he was very successful in reclaiming Byzantine lands and defending against hostile neighbours. Unfortunatley, he fell under the influence of Basil the Macedonian. Basil coerced him into appointing Basil as Co-Emporer. The new Co-Emporer proceeded to murder Michael and seize power.
The Macedonian revival otherwise known as the Byzantine Renaissance marked a period of time in which Byzantium experienced unprecedented wealth, growth and success. The new Macedonian emperors expanded the Orthodox faith to the Slavic peoples and reconquered Syria, Anatolia and Northern Mesopotamia. However, this revival would come to an end with the Great Schism.
Basil II, subjugated Bulgaria ending centuries of warfare and adding valuable territory to the Empire. He also married his sister to Vladimir I of the Kievan Rus’ which converted the northern Slavic peoples to Orthodox Christianity and formed an important alliance.
The Bulgarian Kingdom, a long-time thorn in the side of Byzantium, is finally defeated by Basil II securing the western borders of Byzantium from immediate danger.
After centuries of religious cooperation, the build up theological disagreements comes to a head when the Patriarch of Constantinople and the Pope excommunicate each other. This firmly divides the church into east and west and will prove disastrous for the Byzantines as they now hold no influence over Catholic Europe.
The Byzantine Emperor, Romanos Diogenes, is defeated at the Battle of Manzikert by the Seljuk Turks. The empire is forced to cede most of Anatolia to the Seljuks over the next decade.
Alexios I founded the Komnenian Dynasty during a time when the empire was collapsing due to constant warfare against both the Seljuks and Normans. Upon defeating the Normans he secured the Balkans for the Empire. Focused on retaining the Byzantine holding in Anatolia, Alexios I called on Pope Urban II to aid in the Christian war against the Muslims resulting in the Crusades.
Pope Urban II in response to Alexius I's plea for help against the Muslims calls a crusade to retake the Holy Land.
The Venetians and their rogue crusaders sack Constantinople effectively shattering Byzantium and bringing about the beginning of the end for the empire.