Constantine the Great and Charlemagne suggest themselves for comparison. They were both religious-political actors, just as Muhammad was. All three connected their politics with religion, wrote laws and conducted wars in the name of God; all three understood religion as a practical principal, as the foundation for a sociopolitical unification of people; all three were representatives of well-known theocratic ideals, and each of them left after himself a certain theocratic organization. According to personal qualities, all three were people candidly religious, honest, and free from base vices. And the personal qualities of all three did not safeguard them from abusing the limitless power that fell to their lot. Constantine he Great committed to death his wife and innocent son; Charlemagne massacred 4,500 Saxon prisoners. These evil deeds in and of themselves are more grave than all the evil deeds of Muhammad, and beyond that one must not forget that Charlemagne belonged to a nation that had already 300 years since accepted Christianity, and was brought up in this religion; and Constantine the Great, who had himself converted to Christianity, moreover, lived in a world incomparably more educated than the cultural milieu of Muhammad. Thus comparison of the latter with religious-political heroes of the East and the West of the Christian world turns out to be in favor of the Arabian prophet; and if the Greeks canonized Constantine, and the Latin Charles, then Muslims have all the more basis to reverently esteem the memory of their apostle.
–Vladimir Soloviev, “Muhammad: His Life and Religious Teaching” in Enemies from the East? V.S. Soloviev on Paganism, Asian Civilizations, and Islam. Trans. Vladimir Wozniuk (Evanston, IL: Northwestern University Press, 2007), 209.