The subject of this study is the Early Byzantine Period Illuminated Theological Manuscripts. The primary aim of this study is to identify and classify the themes of Early Byzantine Period illuminated theological manuscripts, analyzing and comparing their styles accordingly, presenting the production materials and determining their place of production. During the museum and library research the Quedlinburg Itala (Ms. Theol. Lat. fol. 485 / LDAB 8476), Ashburnham Pentateuch (Ashburnham Pentateuch MS nouv. acq. lat. 2334 / LDAB 8110), Rabbula Gospel (Rabbula Gospels Cod. Plut. I, 56 / LDAB 115232), Paris Syrian Bible (The Syriac Bible of Paris Cod. syr. 341 / LDAB 115270), St. Augustus Gospel (Cambridge, Corpus Christi College 286 / LDAB 7481), British Library Cannon Tables (London, British Library Add MS 5111 / LDAB 7151) and Cotton Genesis (Lond. Cotton Otho B. IV / LDAB 3242) were analyzed at the outset under the title of Early Byzantine Period Illuminated Theological Manuscripts. The Rossano Gospels (Codex Purpureus Rossanensis / LDAB 2990), Sinope Gospel (Codex Purpureus Sinopensis Paris, Suppl. Gr. 1226 / LDAB 2902) and Vienna Genesis (Vindob. Theol. gr. 31 / LDAB 3078) were addressed separately under the title of Early Byzantine Period Purpura Codices.