“Procopii Caesariensis V.I. ΑΝΕΚΔΟΤΑ Arcana Ηistoria, qui est liber nonus historiarum ex Bibliotheca Vaticana”, Lugduni : Sumpt. Andreae Brugiotti Bibliopolae Romani, 1623. The Famous FIRST EDITION of Procopius Secret History / Aπόκρυφη Iστορία discovered only in early 17th century in the Vatican Library. Folio, pp.[10], xxiij, [1], 135, [1], 142, [20]. Text in Greek with parallel translation in columns. Woodcut initial, chapter ornaments and impressive printer’s devise on title page. Contemporary full vellum, soiled, with light wear along edges. Internally water-stain on fist ~20 sheets, otherwise fine. Crack of internal joint but still firm. Procopius (c.500-after 565) was a prominent Byzantine scholar, he is commonly classified as the last major historian of the ancient world. His Secret History (Ανέκδοτα) deals with 6th century Byzantine history and society. The work claims to expose the secret springs of the Byzantine ruling class. It is highly praised today as a major source. Although its existence was already known from the Suda, which referred to it as Procopiuss "unpublished works", it was discovered only in early 17th century in the Vatican Library and published with the current 1623 edition in Lyon by Niccolò Alamanni. The discovery of Procopius secret history manuscript and its publication changed a lot the understanding of Byzantine middle 6th century society and history. Very Rare.