The Reginensis graecus 1 is the first and only extant volume of what was originally a two-volume set containing the entire Bible in Greek. It was produced in the first half of the tenth century and contains the books Genesis through Psalms. It makes a modest textual contribution to the Septuagint (where its text is generally very similar to that of the Codex Vaticanus, Vat. gr. 1209), but it is famous mainly for its splendid miniatures, which have been separated from the main volume and given their own shelfmark (Reg. gr. 1B), though their folio numbers reflect their positions in the original manuscript. A prefatory poem indicates that the volume was commissioned by one Leo Patrikios, and it is consequently sometimes referred to as the ‘Bible of Leo the Patrician’ or simply the ‘Leo Bible.’