The composite nature of the story makes an identification of the exact site difficult, but one of the narrators (E) seems to have in.
He recites how he had heard of the monarch's Christian profession, diligence in good works and piety, by manifold narrators and common report, but also more particularly from his (the pope's) physician and confidant (medicus et familiaris noster), Master Philip, who had received information from honourable persons of the monarch's kingdom, with whom he had intercourse in those (Eastern) parts.
To the historian it furnishes what is evidently the testimony of an eye-witness on several matters of importance which are neglected by other narrators; and to the student of literature it has the exceptional interest of being one of the prime sources of Shakespeare's historical plays.
The persistent belief on the part of the narrators in the genuineness of their previsions indicates that in some cases there may be a hallucination of memory, analogous to the well known feeling of "false recognition."
We have now reached the most celebrated name among the Arabian caliphs, celebrated not only in the East, but in the West as well, where the stories of the Thousand and One Nights have made us familiar with that world which the narrators represent in such brilliant colours.
Fredegarius (so-called), who probably wrote in the middle of the 7th century, and Paul the Deacon, towards the close of the 8th, supply the saga-like details, which become more minute the farther the narrators are from the action.