* * * * *

We must not believe that the transformation of Rome from a pagan into
a Christian city was a sudden and unexpected event, which took the
world by surprise. It was the natural result of the work of three
centuries, brought to maturity under Constantine by an inevitable
reaction against the violence of Diocletian's rule. It was not a
revolution or a conversion in the true sense of these words; it was
the official recognition of a state of things which had long ceased to
be a secret. The moral superiority of the new doctrines over the old
religions was so evident, so overpowering, that the result of the
struggle had been a foregone conclusion since the age of the first
apologists. The revolution was an exceedingly mild one, the
transformation almost imperceptible. No violence was resorted to, and
the tolerance and mutual benevolence so characteristic of the Italian
race was adopted as the fundamental policy of State and Church.

The transformation may be followed stage by stage in both its moral
and material aspect. There is not a ruin of ancient Rome that does not
bear evidence of the great change. Many institutions and customs still
flourishing in our days are of classical origin, and were adopted, or
tolerated, because they were not in opposition to Christian
principles. Beginning with the material side of the question, the
first monument to which I have to refer is the Arch of Constantine,
raised in 315 at the foot of the Palatine, where the Via Triumphalis
diverges from the Sacra Via.

The importance of this arch, from the point of view of the question
treated in this chapter, rests not on its sculptured panels and
medallions,--spoils taken at random from older structures, from which
the arch has received the nickname of AEsop's crow (_la cornacchia di
Esopo_),--but on the inscription engraved on each side of the attic.
"The S. P. Q. R. have dedicated this triumphal arch to Constantine,
because _instinctu divinitatis_ (by the will of God), and by his own
virtue, etc., he has liberated the country from the tyrant [Maxentius]
and his faction." The opinion long prevailed among archaeologists that
the words _instinctu divinitatis_ were not original, but added after
Constantine's conversion. Cardinal Mai thought that the original
formula was _diis faventibus_, "by the help of the gods," while Henzen
suggested _nutu Iovis optimi maximi_, "by the will of Jupiter."
Cavedoni was