Notes and quotes from Schaff’s History of the Christian Church (emphasis added by me)
Everyone Loves Christmas!
The Christmas festival is the celebration of the incarnation of the Son of God. It is occupied, therefore, with the event which forms the centre and turning-point of the history of the world. It is of all the festivals the one most thoroughly interwoven with the popular and family life, and stands at the head of the great feasts in the Western church year. It continues to be, in the entire Catholic world and in the greater part of Protestant Christendom, the grand jubilee of children, on which innumerable gifts celebrate the infinite love of God in the gift of his only-begotten Son. It kindles in mid-winter a holy fire of love and gratitude, and preaches in the longest night the rising of the Sun of life and the glory of the Lord. It denotes the advent of the true golden age, of the freedom and equality of all the redeemed before God and in God. No one can measure the joy and blessing which from year to year flow forth upon all ages of life from the contemplation of the holy child Jesus in his heavenly innocence and divine humility.
Johnny Come Lately:
…the festival of the birth of the Lord is of comparatively late institution. This may doubtless be accounted for in the following manner:
In the first place, no corresponding festival was presented by the Old Testament, as in the case of Easter and Pentecost.
In the second place, the day and month of the birth of Christ are nowhere stated in the gospel history, and cannot be certainly determined.
Again: the church lingered first of all about the death and resurrection of Christ, the completed fact of redemption, and made this the center of the weekly worship and the church year.
Finally: the earlier feast of Epiphany afforded a substitute. The artistic religious impulse, however, which produced the whole church year, must sooner or later have called into existence a festival which forms the groundwork of all other annual festivals in honor of Christ.
The feast of Epiphany had spread from the East to the West. The feast of Christmas took the opposite course. We find it first in Rome, in the time of the bishop Liberius, who on the twenty-fifth of December, 360…
(“The human mind is, so to speak, a perpetual forge of idols.” John Calvin, Institutes, 1.XI.8)
Christmas was introduced in Antioch about the year 380; in Alexandria, where the feast of Epiphany was celebrated as the nativity of Christ, not till about 430. Chrysostom, who delivered the Christmas homily in Antioch on the 25th of December, 386, already calls it, notwithstanding its recent introduction (some ten years before), the fundamental feast, or the root, from which all other Christian festivals grow forth.
Of Pagan Origin:
The Christmas festival was probably the Christian transformation or regeneration of a series of kindred heathen festivals—the Saturnalia, Sigillaria, Juvenalia, and Brumalia—which were kept in Rome in the month of December, in commemoration of the golden age of universal freedom and equality, and in honor of the unconquered sun, and which were great holidays, especially for slaves and children. (Schaff’s footnote: The Satumalia were the feast of Saturn or Kronos, in representation of the golden days of his reign, when all labor ceased, prisoners were set free, slaves went about in gentlemen’s clothes and in the hat (the mark of a freeman), and all classes gave themselves up to mirth and rejoicing. The Sigillaria were a festival of images and puppets at the close of the Saturnalia on the 21st and 22d of December, when miniature images of the gods, wax tapers, and all sorts of articles of beauty and luxury were distributed to children and among kinsfolk. The Brumalia, from bruma (brevissima, the shortest day), had reference to the winter solstice, and the return of the Sol invictus.)
The OG Festival: All About the Incarnation
The feast of Epiphany on the contrary, on the sixth of January, is older… It refers in general to the manifestation of Christ in the world, and originally bore the twofold character of a celebration of the birth and the baptism of Jesus. After the introduction of Christmas, it lost its reference to the birth. The Eastern church commemorated on this day especially the baptism of Christ, or the manifestation of His Messiahship, and together with this the first manifestation of His miraculous power at the marriage at Cana. The Westem church, more Gentle-Christian in its origin, gave this festival, after the fourth century, a special reference to the adoration of the infant Jesus by the wise men from the east, under the name of the feast of the Three Kings, and transformed it into a festival of Genthe missions; considering the wise men as the representatives of the nobler heathen world. Thus at the same time the original connection of the feast with the birth of Christ was preserved. Epiphany forms the close of the Christmas Cycle. It was an early custom to announce the term of the Easter observance on the day of Epiphany by the so-called Epistolae paschales, or gravmmata pascavlia. This was done especially by the bishop of Alexandria, where astronomy most flourished, and the occasion was improved for edifying instructions and for the discussion of important religious questions of the day.