This originated as part of building a basic persona guide, written for the Midrealm Pursuivant’s Handbook (located here). Within that guide, I discussed the basic history of the Eastern Empire, as well as basic points of clothing, weaponry, literary references, political groups, religious information, as well as people within the Empire of note. This guide is not meant to be exhaustive, but to create a point to jump off from to start your own research. That said, I plan on writing more detailed information going through the history, clothing, and the like from century to century. A reminder that while this list is not exhaustive, I would also like to make the point that Byzantium is not a monolith, meaning that just because something was true in the 6th century in Constantinople, did not make it even a long-standing tradition in the backwaters of the Empire in the 13th century. Look at your sources critically.
As a continuation of the Western Roman Empire, the Eastern Roman empire was vast, stretching at one point from the banks of the Bosphorus to the edges of the Iberian Peninsula. Founded as a colony in 657 BCE by the ancient Greek Empire, Byzantion, the jewel of the Eastern Roman Empire, came into its own during the third century CE under the Roman emperor Diocletian. Diocletian set up a system where he would rule the Western half of the Empire with a junior emperor, and Galerius, who ruled the Eastern half with Constantine as his junior emperor. This system was called the tetrarchy. The collapse of the tetrarchy system on the abdication of Diocletian, and his junior emperor, enabled Constantine the Great to become emperor of the Eastern Roman Empire.
People of the Eastern Roman Empire considered themselves to be Roman. By the time of Justinian (himself a native Latin speaker), however, most people within the city spoke a form of Greek, Koine (Alexandrian dialect, common Attic, Hellenistic or Biblical Greek), though the language of the court was Latin until the reign of Heraclius (610 CE to 641).
Under Constantine, the financial and military systems that contributed to the fall of the Western Empire stabilized in the East. In 324 CE, Constantine moved the capital to Constantinople. 1203 CE brought the Fourth Crusade to Constantinople’s walls, leading to the sack of the city by the Venetians. The Eastern Roman Empire fell to the Ottomans in 1453 CE, and Byzantium was renamed Istanbul.
Clothing: The Eastern half of the Roman Empire wore clothing that followed the same basic
patterns as the Western half of the Roman Empire. This style did not depart from that until the 10th century. Both men and women wore tunics, with both wearing at least an under and over tunic in the earlier parts of the timeline, trimmed similarly to the clothing of their compatriots on the Western side. In the Eastern Empire, though, the trim expanded to a sartorial riot of multi-colored silks. Trim was concentrated on necklines, cuffs, and hems through most of the span of the Empire, even on the lower classes’ garments. Social rank was determined by the type of fabrics, with silk being worn by the upper classes. More can be seen here.
Weapons: Originally using weapons from their Western compatriots, the Eastern Roman Empire expanded their weaponry from spears, axes, and daggers to cavalry, lead-weighted darts, and Greek fire. The military might of the Empire was augmented by mercenaries in the 10th century, which they called the Varangian Guard, an elite barbarian guard which was originally comprised of 6000 Kievan Rus sent to Basil II from Vladimir of Kiev. The Varangian Guard is thought to have been disbanded after the sack of Constantinople by the forces of the Fourth Crusade in 1204 CE.
Literature: The following literary references are items from within period. History of the Wars and Secret History by Procopius, Corpus Juris Civilis (Codex Justinianus) by Justinian I, De Ceremoniis by Constantine VII Porphyrogennetos, “O, City of Byzantium” by Niketas Chionates, the writings of John Skylitzes and Michael Psellus, Alexiad by Princess Anna Komnene, the religious writings of John Chrysostom.
Politics: Four political parties started as chariot hooligans and teams in the 6th century: the
Greens, Blues, Reds, and Whites. The Reds and Whites were subsumed by the Greens and the Blues, and as time elapsed, these two political parties became largely ceremonial after the 7th century. Under Justinian I and Theodora, women began to enjoy more freedoms, such as being allowed to own businesses and property, and young girls could be educated.
Religion: Under Constantine the Great, Christianity flourished, and though it was not the state religion, it did have imperial preference. Justinian I and Theodora built Hagia Sophia during their reign, with Theodora favoring Miaphysitism and Justinian favoring Chalcedonian Christianity. At the beginning of the 8th century, there arose a feeling among some people of the Byzantine Empire that religious statues and religious paintings that decorated churches were becoming the object of worship in and of themselves. Thus, the images, or icons, were interfering with the true goal of worship. An iconoclast movement arose which sought to “cleanse” the church by destroying all religions icons, with a second period of Iconoclasm occuring in the 9th century.
The Great Schism between Eastern and Western churches (what we know of now as Eastern
Orthodox and Roman Catholicism) occurred in 1054 CE.
Important Places: Blachernae Palace, Boukoleon Palace, Hagia Sophia, Great Palace of Constantinople, the Hippodrome, Mausoleum of Galla Placidia, Basilica of San Vitale
Important People: Constantine the Great, Belisarius, Narses, Justinian I, Theodora, Constantine VII Porphyrogennetos, Alexios I, Constantine XI