Justinian I

Justinian I or Iustinian I (/dʒʌˈstɪniən/; Latin: Flavius Petrus Sabbatius Iustinianus Augustus, Greek: Φλάβιος Πέτρος Σαββάτιος Ἰουστινιανός Flávios Pétros Sabbátios Ioustinianós) (c. 482 – 14 November 565), traditionally known as Justinian the Great and also Saint Justinian the Great in the Eastern Orthodox Church, was a Byzantine (East Roman) emperor from 527 to 565. During his reign, Justinian sought to revive the empire's greatness and reconquer the lost western half of the historical Roman Empire. Justinian's rule constitutes a distinct epoch in the history of the Later Roman empire, and his reign is marked by the ambitious but only partly realized renovatio imperii, or "restoration of the Empire".

Because of his restoration activities, Justinian has sometimes been called the "last Roman" in modern historiography. This ambition was expressed by the partial recovery of the territories of the defunct western Roman empire. His general, Belisarius, swiftly conquered the Vandal kingdom in North Africa, re-extending Roman control to the Atlantic Ocean. Subsequently Belisarius, Narses, and other generals conquered the Ostrogothic kingdom, restoring Dalmatia, Sicily, Italy, and Rome to the empire after more than half a century of rule by the Ostrogoths. The prefect Liberius reclaimed most of southern Iberia, establishing the province of Spania. These campaigns re-established Roman control over the western Mediterranean, increasing the Empire's annual revenue by over a million solidi. During his reign Justinian also subdued the Tzani, a people on the east coast of the Black Sea that had never been under Roman rule before.

Byzantine Empire

The Byzantine Empire, sometimes referred to as the Eastern Roman Empire, was the continuation of the Roman Empire in the East during Late Antiquity and the Middle Ages, when its capital city was Constantinople (modern-day Istanbul, originally founded as Byzantium). It survived the fragmentation and fall of the Western Roman Empire in the 5th century AD and continued to exist for an additional thousand years until it fell to the Ottoman Turks in 1453. During most of its existence, the empire was the most powerful economic, cultural, and military force in Europe. Both "Byzantine Empire" and "Eastern Roman Empire" are historiographical terms created after the end of the realm; its citizens continued to refer to their empire as the Roman Empire (Ancient Greek: Βασιλεία τῶν Ῥωμαίων, tr. Basileia tôn Rhōmaiōn; Latin: Imperium Romanum), or Romania (Ῥωμανία), and to themselves as "Romans".

Several events from the 4th to 6th centuries mark the period of transition during which the Roman Empire's Greek East and Latin West divided. Constantine I (r. 324–337) reorganised the empire, made Constantinople the new capital, and legalised Christianity. Under Theodosius I (r. 379–395), Christianity became the Empire's official state religion and other religious practices were proscribed. Finally, under the reign of Heraclius (r. 610–641), the Empire's military and administration were restructured and adopted Greek for official use instead of Latin. Thus, although the Roman state continued and Roman state traditions were maintained, modern historians distinguish Byzantium from ancient Rome insofar as it was centred on Constantinople, oriented towards Greek rather than Latin culture, and characterised by Orthodox Christianity.

Roman Empire

The Roman Empire (Latin: Imperium Rōmānum; Classical Latin: [ɪmˈpɛ.ri.ũː roːˈmaː.nũː] Ancient and Medieval Greek: Βασιλεία τῶν Ῥωμαίων, tr. Basileia tōn Rhōmaiōn) was the post-Roman Republic period of the ancient Roman civilization, characterized by government headed by emperors and large territorial holdings around the Mediterranean Sea in Europe, Africa and Asia. The extended city of Rome was the largest city in the world c. 100 BC – c. 400 AD, with Constantinople (New Rome) becoming the largest around 500 AD, and the Empire's populace grew to an estimated 50 to 90 million inhabitants (roughly 20% of the world's population at the time). The 500-year-old republic which preceded it was severely destabilized in a series of civil wars and political conflict, during which Julius Caesar was appointed as perpetual dictator and then assassinated in 44 BC. Civil wars and executions continued, culminating in the victory of Octavian, Caesar's adopted son, over Mark Antony and Cleopatra at the Battle of Actium in 31 BC and the annexation of Egypt. Octavian's power was now unassailable and in 27 BC the Roman Senate formally granted him overarching power and the new title Augustus, effectively marking the end of the Roman Republic.