The Liber Testamentorum, or Book of Testaments of the Cathedral of Oviedo, is one of the most valuable codices housed in the Cathedral Archive of Oviedo. Dating back to the 12th century, it was commissioned by Bishop Pelayo of Oviedo.

This cartulary, a collection of documents in book form, contains a total of eighty-seven legal documents, including privileges granted to the cathedral seat of Oviedo by monarchs and pontiffs.

Originally, the book comprised 113 pages of parchment, written in Visigothic typography. Its illustrations, featuring miniatures, contribute to its status as one of the jewels of peninsular Romanesque illumination.

The book features several miniatures that occupy entire pages, including one depicting the monarch Alfonso II the Chaste, shown kneeling in a gesture of piety in a lower register. Beside him stands his assistant, the armiger regis (bearer of the royal arms), who carries the King’s arms. Both figures are flanked by Holy Mary, with her head raised and turned towards the Pantocrator, and the Archangel Saint Michael, who wields the lance used to strike the dragon. These figures serve as intercessors between the king and the divine. In the upper register, the celestial scene is depicted: Christ, enclosed in a mystical mandorla, is supported by the evangelists, while a complete apostolate is portrayed beneath the semicircular arches.