Poemas del río Wang has a post on an interesting topic: “since when is Byzantium called Byzantium?”
The “Byzantine” Empire in reality never existed under this name, which put roots and is exclusively used in historiography. The term was coined about a century after the fall of the Roman Empire – as it was really called – by a German humanist historian, Hieronymus Wolf.
Wolf learned self-taught Greek. In 1549 he published the first translation of Demosthenes’ speeches. From 1551 he worked the Augsburg Fugger library, where he catalogued the medieval Greek manuscripts brought from Venice. In 1557 he published his main work, the Corpus Historiae Byzantinae, compiled from the Greek sources in the Augsburg library, with which he unintentionally rewrote world history. When in the early 17th century the compilation of a similar summary from the surviving Constantinople sources was encouraged by Louis XIV of France, it obviously had to be based on Wolf’s work, so that Philippe Labbé, the Jesuit scholar leading the project did not even try to find a new title for the 34-volume collection: it was also published as Corpus Scriptorum Historiae Byzantinae. The scholars dealing with the late Roman Empire, centered on Constantinople, all adopted this terminology (e.g. Corpus Scriptorum Historiae Byzantinae, Bonn 1822-1897). The adjective “Byzantine”, which during the Enlightenment spread worldwide, especially due to the writings of Montesquieu, was impossible to be detached from the (late) Roman Empire. And the adjective was also associated with an explicitly negative connotation, which was deduced from the supposed qualities of state power: courtly intrigues, complicated bureaucracy, incomprehensible and over-decorated ceremoniality and fraudulent diplomacy.
It continues with fascinating historical details and the usual gorgeous images (I spent quite a while staring at the 1422 map of Constantinople: “This is the oldest surviving map of the city, and the only one made before the Turkish conquest”), and points out that the Rimini tomb of “one of the last great Greek Neoplatonic philosophers, Georgios Gemistus Plethon” has an inscription beginning:
[The mortal remains of the Byzantine Gemistus Plethon, the greatest philosopher of his age]
[…] If we assume that the tomb inscription was not made after Wolf’s work of 1557 (and the tombstone-carver did not keep pace with the latest scientific research), then we must also assume that the term “Byzantine” already existed before 1557, as a typical Renaissance hyper-classicism (like Istropolis instead of Posonium), but it was only applied to the city, and not to the state. Wolf was probably aware of this use, and as he tried to draw a caesura between the ancient and medieval Greek literature and sources, he adopted the term “Byzantine”, which was later extended on the basis of his work to the Constantinople-centered Roman Empire.
I would quibble, however, with the post’s final sentence: “Nowadays, if anybody talks about the Roman Empire in connection with the period between the 6th and 15th century, he will shock his listeners just as much as if he used the term of Byzantine Empire in those very centuries.” For a long time now, serious scholars have talked about the Eastern Roman Empire and used the term “Byzantine” with restraint, mainly because it is so familiar; you’d have to have ignored the subject for decades to be shocked by such usage.