Mystikos

The mystikos (Greek: μυστικός, "the secret one") was an important Byzantine office of the imperial chancery from the 9th through to the 15th centuries. Its initial role is unclear; he was probably the Byzantine emperor's private secretary. In time, the office also exercised judicial duties. It became an important fiscal official in the Komnenian period, and remained one of the highest-ranking state offices into the Palaiologan period as well.

The office first appears in the reign of Emperor Basil I the Macedonian (r. 867–886), when it was held by Leo Choirosphaktes. The original function of the office is unclear.Franz Dölger regarded the mystikos as the emperor's private secretary, while Nicolas Oikonomides considered him already at that stage as a judicial official.

Due to their proximity to the emperor, the holders of the office had considerable power. Already under Emperor Leo VI the Wise (r. 886–912), a mystikos became Patriarch of Constantinople: Nicholas I Mystikos. Trusted by the emperors, the mystikoi are thus attested as occupying various important offices: at times they exercised the duties of a protasekretis, various judicial duties, or served as heads of the establishment of the imperial bedchamber (koitōn). The office rose to particular prominence under Emperor Manuel I Komnenos (r. 1143–1180), when the mystikos was given charge of the imperial palace and the emperor's treasury, thus controlling not only the flow of salaries to the various imperial officials, but also the patronage and donations from the imperial purse to the Church. The office remained important in the 13th century, when at least one of its holders held the rank of pansebastos. The title's functions at this time, however, are again unclear. The office remains attested up to the end of the Byzantine Empire in the 15th century.

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