The great uncial [N1] codices or four great uncials are the only remaining uncial codices that contain (or originally contained) the entire text of the Greek Bible (Old and New Testament). Only four great codices have survived to the present day: Codex Vaticanus (abbreviated: B), Codex Sinaiticus (א), Codex Alexandrinus (A), and Codex Ephraemi Rescriptus (C).
circa 320 CE
Codex Sinaiticus is one of the world's most remarkable books. Written in Greek in the fourth century, it is the oldest surviving complete New Testament, and one of the two oldest manuscripts of the whole Bible. It also stands out as a complex and beautiful artefact. It is one of the most important texts for studying ancient Greek translations of the "Hebrew Bible", and for the study of the New Testament and the two other early Christian writings it contains, the "Epistle of Barnabas" and the "Shepherd of Hermas". For many centuries, it was preserved in St Catherine's Monastery on Mount Sinai.
circa 325 CE
Codex Vaticanus is regarded as the oldest extant manuscript of the Greek Bible (Old and New Testament). The Codex is named after its place of conservation in the Vatican Library, where it has been kept since at least the 15th century. It is written on 759 leaves of vellum in uncial letters and has been dated palaeographically to the 4th century. The manuscript became known to Western scholars as a result of correspondence between Erasmus and the prefects of the Vatican Library.
circa 420 CE
Codex Alexandrinus is the most valuable Greek manuscript of the Old and New Testaments, so named because it was brought to Europe from Alexandria and had been the property of the patriarch of that see. It derives its name from Alexandria where it resided for a number of years before it was brought by the Eastern Orthodox Patriarch Cyril Lucaris from Alexandria to Constantinople. Today, it rests along with Codex Sinaiticus in one of the showcases in the Ritblat Gallery of the British Library.
circa 450 CE
Codex Ephraemi Rescriptus is a fifth-century Greek manuscript of the Bible. The manuscript is called Codex Ephraemi Rescriptus because (a) it is a codex, i.e., a handmade book; (b) its parchment has been recycled. The uncial writing is continuous, with the punctuation consisting only of a single point, as in codices Alexandrinus and Vaticanus.
[N1] Uncial is a majuscule script (written entirely in capital letters) commonly used from the 4th to 8th centuries CE by Latin and Greek scribes. Uncial letters were used to write Greek, Latin, and Gothic.