It is located inside the chapel of Nuestra Señora del Rey Casto (Our Lady of the Chaste King), where many members of the royalty of Asturias and León were buried during the Early Middle Ages. The original royal pantheon was located inside the church of Nuestra Señora del Rey Casto, attached to Oviedo Cathedral, and had been built at the request of King Alfonso II the Chaste, in the 9th century.

The primitive royal pantheon and the primitive church of Nuestra Señora del Rey Casto were demolished at the beginning of the 18th century, due to their poor state of conservation, on the initiative of Tomás Reluz, Bishop of Oviedo, and both were subsequently rebuilt and consecrated in 1712.

The members of the Asturian-Leonese royalty who are currently buried in the Baroque urns of the Pantheon of Kings in Oviedo Cathedral, according to various historians.