The unity of the Empire gave Christianity its chance. Through the connection of Eurasia from the Euphrates to the Atlantic by magnificent roads, communication between peoples followed the lines of least resistance. Happily for the future of Christianity, the early missionaries travelled westward, in the wake of the dispersed Jews, along the Mediterranean seaboard, and thus its fortunes became identified with the civilizing portion of mankind. Had they travelled eastward, it might have been blended with Buddhism, or, as its Gnostic phases show, become merged in Oriental mysticism. The story of progress ran smoothly till A. D. 64, when we first hear of the "Christians"--for by such name they had become known--in "profane" history, as it was once oddly called. Tacitus, writing many years after the event, tells how on the night of the 18th July, in the sixty-fourth year of our era, a fierce fire broke out in Rome, causing the destruction of magnificent buildings raised by Augustus, and of priceless works of Greek art. Suspicion fell on Nero, and he, as has been suggested, was instigated by his wife Poppaea Sabina, an unscrupulous woman, and, according to some authorities, a convert to Judaism, "to put an end to the common talk, by imputing the fire to others, visiting, with a refinement of punishment, those detestable criminals who went by the name of Christians. The author of that denomination was Christus, who had been executed in the time of Tiberius, by the procurator, Pontius Pilate." Tacitus goes on to describe Christianity as "a pestilent superstition," and its adherents as guilty of "hatred to the human race." The indictment, on the face of it, seems strange, but it has an explanation, although the Christians were brutally murdered on the charge of arson, and not of superstition. So far as religious persecution went, they suffered this first at the hands of Jews, the Empire intervening to protect them. Broadly speaking, the Roman note was toleration. Throughout the Empire religion was a national affair, because it began and ended with the preservation of the State. Thereupon it was the binding duty--_religio_--of every citizen to pay due honour to the protecting gods on whose favour the safety of the State depended. That done, a man might believe what he chose. Polytheism is, from its nature, easy-going and tolerant; so long as there was no open opposition to the authorized public worship, the worshipper could explain it any way he chose. In Greece a man "might believe or disbelieve that the Mysteries taught the doctrine of immortality; the essential thing was that he should duly sacrifice his pig." In Rome, that vast Cosmopolis, "the ordinary pagan did not care two straws whether his neighbour worshipped twenty gods or twenty-one." Why should he care?