Mohammedism in the same way conquers those Pagan creeds which are morally inferior to it.

The Seljuk and the Ottoman Turks were Pagans, but adopted the religion of Tartars and Persians whom they subjugated, because it was superior and was blended with a superior civilization; exactly as the German conquerors of the Western Empire of Rome adopted some form of Christianity.
But if it is true that _the sword_ of Mohammed was the influence which subjected Arabia, Egypt, Syria and Persia to the religion of Islam, it is no less true that the Roman empire was finally conquered to Christianity by the sword.

Before Constantine, Christians were but a small fraction of the empire.

In the preceding century they had gone on deteriorating in good sense and most probably therefore in moral worth, and had made no such rapid progress in numbers as to imply that by the mere process of conversion they would ever Christianize the empire.

That the conversion of Constantine, such as it was, (for he was baptized only just before death,) was dictated by mere worldly considerations, few modern Christians will deny.