Santa Maria in Turri

[d] In an eighth-century description of the Vatican basilica,[3] it is called S. Maria quae nova dicitur,[e] which helps in dating the origin of the structure.

S. Maria in turri was located at the left of the entrance; at the right in the corner, S. Apollinaris; then beyond those two, facing them in the portico immediately in front of the basilica, S. Vincentius, which lay immediately to the right of the corner; and S. Maria de febre, situated to the left where the ancient secretarium was, which was also called oratorium S. Gregorii ("oratory of Saint Gregory") because of its proximity to his tomb.

[4] During the coronation, the king about to be crowned would greet the pope in the square standing above the steps, would go into the church, and, with his hand on the book of the Gospels, would take a personal oath of fidelity.

[5] That tower was built, according to the Liber Pontificalis, by Pope Stephen II (752–757), and reportedly "covered in pieces of gold and silver" (by which is probably meant mosaic decorations in those colors),[1] and provided with three bells, which were a defensive alarm measure.

That same mosaic is mentioned in Barberini Codex XXXIV, 50,[7] in which the church is referred to by the title Ecclesia S. Mariae in turri supra gradus anteriores scalarum veteris basilicae Vaticanae, cuius frons musivo opere ornata fuit a Sancto Paulo papa primo, qui sedit anno 757.

[f] On the church itself, there was a dedicatory inscription underneath a mosaic work on the facade, which read: Christe tibi sit honor Paulus quod decorat opus.

It was for that occasion that an inscription was carved on the altar in Leonine verse, later reported by Grimaldi: Est in honore piae domus ista sacrata Mariae Hoc Innocenti te presule perficienti Cui suberat[1] On 8 June 1155, Adrian IV crowned Frederick Barbarossa Holy Roman Emperor at the ancient Basilica of St. Peter.