
There is a theory that Christians in
the fourth century assigned December 25th (the Winter Solstice on the Julian
calendar) as Christ's birthday (and thus Christmas) because pagans already observed
this day as a holiday. This theory is much disputed, as the dates of Saturnalia
are not coincident with Christmas. A more refined argument is that Christmas
was set on the feast of Sol Invictus, which was on December 25, and which had
supplanted Saturnalia. However, others claim that early Christians independently
came up with the date of December 25th based on a Jewish tradition of the "integral
age" of the Jewish prophets (the idea that the prophets of Israel died
on the same dates as their birth or conception), and a miscalculation of the
date of Jesus' death. A theory has been advanced that the establishment of the
feast of Sol Invictus on December 25 was an attempt by Aurelian to co-opt the
day already celebrated by Christians for a pagan festival.
It's far less important than those historical
debates, but there's also a small disagreement about why the church later chose
Dec. 25 for Christmas. Two main theories compete.
One notes that in A.D. 274, the Roman
Emperor Aurelian inaugurated Dec. 25 as the pagan "Birth of the Unconquered
Sun" celebration, at the calendar point when daylight began to lengthen.
Supposedly, Christians then borrowed the date and devised Christmas to compete
with paganism.

Aurelian's empire seemed near collapse,
so his festival proclaimed imperial and pagan rejuvenation. Prior to 274 there's
no record of a major sun cult at the Northern Hemisphere's winter solstice (the
year's shortest day, which actually occurs before Dec. 25).
William Tighe, a church history specialist
at Pennsylvania's Muhlenberg College, champions the exact opposite theory.
Aurelian almost certainly created "a
pagan alternative to a date that was already of some significance to Roman Christians,"
Tighe wrote last December in Touchstone, a Chicago-based magazine for Catholic,
Orthodox and Protestant traditionalists.

True, the Christians later appropriated
Aurelian's festival into their Christmas. But Dec. 25 "appears to owe nothing
whatsoever to pagan influences," Tighe asserted. He said the pagans-first
theory originated only three centuries ago in the writings of Protestant historian
Paul Ernst Jablonski and Catholic monk Jean Hardouin.
Tighe acknowledged that the first hard
evidence of Christmas occurring on Dec. 25 isn't found until A.D. 336 and the
date only became a fixed festival in Constantinople in 379.