Was Jesus born on December 25th?

From time to time it is falsely claimed - or, at the very least - assumed, that Christians celebrate the birth of Jesus on December 25th because earlier Christians supplanted the pagan feast of Sol Invictus (the unconquerable sun) with the Incarnation of the Christ.  This is - to be blunt - quite incorrect.

Consider this (emphases original):

Among the many issues discussed – and debated – on Jesus’ birth, is the Deus Sol Invictus festival and the theory according to which, the 25th of December was a date chosen by Christians to overlap a pagan festival with the celebrations of the Lord’s nativity. However, in his book, Michele Loconsole attempts to discredit this stereotype. “Having studied the sources of the time, it seems that exactly the opposite occurred. In actual fact, the pagan festival of Deus Sol Invictus was timed, or rather delayed, until the 25th of December, in an attempt to draw attention away from, or replace, the Christian festival celebrating the Lord’s Christmas.” Before 354 A.D., during the reign of Licinius, the festival was celebrated in Rome on 19 December. We can also say that this extremely ancient astronomical festival was celebrated in Rome and elsewhere at different times of the year, often between 19 and 22 October. The oldest source that discusses Christmas being on 25th December, is Hippolytus of Rome, who in 204, referred to the festival celebrated by Christians. The cult of the sun god was introduced to Rome by the emperor Heliogabalus, between 218 and 222, and was made official in 274 by emperor Aurelian, who on 25 December of that year, consecrated a temple dedicated to the cult of Sol invictus. And given that the feast of Sol Invictus was not celebrated by pagans only on 25 December and that this date was only given precedence over the others in the second half of the 4th century, “can’t we legitimately assume that the festival of Sol Invictus in the Roman empire’s calendar was the result of a conscious wish of the establishment to replace or at least draw attention away from the Christian festival of Christmas, which had been definitely celebrated in Rome on 25 December for at least the previous 70 years?”

There you have it.  Please be kind in reminding the secularists of the actual historical fact.

But what of the claim that shepherds didn't pasture their sheep in the winter and so couldn't have encountered the angels or the Holy Family on December 25th?  Where else would the sheep be?  In the shepherd's house?

It should be remembered that there are (so far as I know) three kinds of sheep: sheep with white wool; sheep with white and black wool; and sheep with black wool (remember Ba Ba Black Sheep?).  It seems that each of these kids of sheep were treating differently under Jewish law (emphases original:

Then there is a third kind. These were flocks of sheep with dark, if not pitch black, wool. The author considers this type of flock to be more unusual than the other two kinds. According to Loconsole’s historical research, these sheep were treated in a special way. They were seen as “impure” animals, so impure that they were not allowed to seek refuge after nightfall either in towns or even in outlying areas. Their existence, according to Jewish law, had to be permanently out in the open; and it would be fair to assume that this would be in places that were not far from their usual pasture. Their treatment was necessarily shared by their shepherds. It was impossible then, as it is now, to abandon flocks to their fate, even if winter nights in the hills of the Middle East can be far from comfortable. Therefore, if this was the situation in Israel during Jesus’ time, the presence of shepherds near the cave and manger was not a mere invention (and why would it be? The shepherds certainly did not add any glamour to the event) of the gospel according to Luke.

Again, please kind in correcting the secularists.  And your poorly informed fellow believers.