s Invicti_ was probably first celebrated in Rome by order
of the Emperor Aurelian (270-5), an ardent worshipper of the Syrian
sun-god Baal.{21} With the _Sol Invictus_ was identified the figure of
Mithra, that strange eastern god whose cult resembled in so many ways the
worship of Jesus, and who was at one time a serious rival of the Christ
in the minds of thoughtful men.[6]{22} It was the sun-god, poetically
and philosophically conceived, whom the Emperor Julian made the centre of
his ill-fated revival of paganism, and there is extant a fine prayer of
his to "King Sun."{23}

What more natural than that the Church should choose this day to
celebrate the rising of her Sun of Righteousness with healing in His
wings, that she should strive thus to draw away to His worship some
adorers of the god whose symbol and representative was the earthly sun!
There is no direct evidence of deliberate substitution, but at all events
ecclesiastical writers soon after the foundation of Christmas made good
use of the idea |24| that the birthday of the Saviour had replaced the
birthday of the sun.[7]

Little is known of the manner in which the _Natalis Invicti_ was kept; it
was not a folk-festival, and was probably observed by the classes rather
than the masses.{24} Its direct influence on Christmas customs has
probably been little or nothing. It fell, however, just before a Roman
festival that had immense popularity, is of great importance for our
subject, and is recalled by another name for Christmas that must now be
considered.

III. The Provencal _Calendas_ or _Calenos_, the Polish _Kolenda_, the
Russian _Kolyada_, the Czech _Koleda_ and the Lithuanian _Kalledos_, not
to speak of the Welsh _Calenig_ for Christmas-box, and the Gaelic
_Calluinn_ for New Year's Eve, are all derived from the Latin _Kalendae_,
and suggest the connection of Christmas with the Roman New Year's Day,
the Kalends or the first day of January, a time celebrated with many
festive customs. What these were, and how they have affected Christmas we
shall see in some detail in Part II.; suffice it to say here that the
festival, which lasted for at least three days, was one of riotous life,
of banqueting and games and licence. It was preceded, moreover, by the
_Saturnalia_ (December 17 to 23) which had many like features, and must
have formed practically one festive season with it. The word _Saturnalia_
has become so familiar in modern usage as to suggest sufficiently