De Ceremoniis

The De Ceremoniis (fully De cerimoniis aulae Byzantinae) is the conventional Latin name for a book of ceremonial protocol at the court of the Byzantine emperors in Constantinople. Its Greek title is often cited as Ἔκθεσις τῆς βασιλείου τάξεως ("Explanation of the Order of the Palace"), taken from the work's preface, or Περὶ τῆς Βασιλείου Τάξεως ("On the Order of the Palace"). In non-specialist English sources, it tends to be called the Book of Ceremonies of Constantine VII Porphyrogennetos (variably spelt), a formula used by writers including David Talbot Rice and the modern English translation.

It was written or at least commissioned by Emperor Constantine VII (reigned 913-959), probably around 956-959. The compilation of Rep. I 17 (Leipzig, Universitätsbibliothek) was partially revised later under Nikephoros II (963-969), perhaps under the supervision of Basil Lekapenos, the imperial parakoimomenos, and it also contains earlier descriptions of the 6th century.

One of the book's appendices are the Three Treatises on Imperial Military Expeditions, a war manual written by Constantine VII for his son and successor, Romanos II.

In its incomplete form chapters 1-37 of book I describe processions and ceremonies on religious festivals (many lesser ones, but especially great feasts like the Elevation of the Cross, Christmas, Epiphany, Palm Sunday, Good Friday, Easter and Ascension Day and saint's days like St Demetrius, St Basil etc. often extended over many days), while chapters 38-83 describe secular ceremonies or rites of passage like coronations (38-40), weddings (39,41), births (42), funerals (60), or the celebration of war triumphs during feasts at the Hippodrome like Lupercalia (73).

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