This small prayer book was once owned by the Holy Roman Emperor Otto III (980−1002). Although it hardly stands out when compared with other luxuriously illuminated manuscripts, it was intended for the sovereign’s private devotion and is one of only two royal prayer books from the early Middle Ages to survive. It was probably commissioned after the year 984, presumably by Archbishop Willigis of Mainz, when the four-year-old Otto was committed to the care of his mother and grandmother, the empresses Theophanu and Adelaide, after his father’s death. The manuscript contains three portraits of Otto. Following a miniature that shows the Crucifixion of Jesus, the first of these depicts the young monarch praying between Saint Peter and Saint Paul. The second shows him kneeling in front of Christ, who is sitting enthroned within the mandorla (almond-shaped ornamental motif). The third (dedicatory) painting shows Otto on his throne receiving the prayer book from a cleric. The texts of the prayers are written in Carolingian minuscule in gold ink on purple ground. It is noteworthy that the parchment itself was not soaked in purple ink, as was customary in the ninth century, but purple fields framed by narrow strips of gold were applied on every page. The subsequent history of the book remains mostly unknown. It was discovered in the 19th century in the library of the noble Schönborn family in Schloss Weißenstein in Pommersfelden, Bavaria. It was acquired by the Bavarian State Library in 1994.