Or, it would be some sections of Abbasid Baghdad or parts of Moorish Spain.
Regarding the Prophet and cross-religious boundaries... I guess nobody here has done much interfaith work IRL? Because if you have, you know that if two faiths are both committed to the idea that their teachings relate to the "Real, Ultimate Nature of Things" then they will take a powerful interest in each others' teachings, and tend to regard each others' highest figures as intellectual authorities (though not necessarily right for that). Consider that many Christian thinkers cited Avicenna, and much Ottoman law cited cases from Orthodox ecumenical rules as authoritative.
The idea that, in a medieval setting, members of one faith would just say that the leader of another faith is bogus without anything to say or without a perspective on the Real, Ultimate Nature of Things is not very tenable, unless there is a strong political motivation to make such a claim. But from a purely intellectual position, Medieval Christian thinkers may have thought their Muslim counterparts were implicitly worshipping demons, but they at least thought they were worshipping very smart demons with lots of interesting knowledge, a la Faustus.
Which was the whole point. There is a big difference between thinking another religion has aspects or teachings that are worthwhile as compared to thinking another religion is producing theology the equal of your own faith and prophets who are the equally as valid as your own religious leaders.
I think of it in a similar way to how Christians revere the Jewish prophets, but place Jesus above them all, or how the Muslims believe Jesus was a messenger of god while rejecting the claims of his divinity and in turn place Muhammad above him.
