Not a one :-)

I think it would be silly to only pick on Christianity here. Humans have surely been celebrating the same times of the year since before we have record of these celebrations.

Basically every traditional holiday is a remnant of a celebration of an equinox or solstice. Christianity surely stole Christmas from pre-Christian religions, but those religions also likely stole their holidays from religions that pre-date them.

All religions have similarities, partly what makes them all stupid asf and hypocritical especially when they call eachother out

This is a cynical interpretation of how Christmas originated. Like it designed by a committee that pre-planned everything with malicious intent. More likelihood, there were just some practices that hold that were holdovers from a pre Christian past but now being used to honor the Christian God. Christmas traditions vary region to region. It was something just happened from the ground up and organically.

Christmas was not created to "smother" Saturnalia, when Rome became Christian they didnt celebrate the holiday because it was closely associated with Romans gods. It was important to their culture though, so it adopted Christian themes and carried on the traditions that actually mattered to the people, like feasting and gift giving.

Though there’s no reference to observances, Easter is a pretty obvious progression from scripture since the Last Supper was a Passover dinner (not a modern Seder, that tradition developed later) and is placed in the year accordingly. This is why its placement in the Gregorian Calendar shifts from year to year, because it is dated from the lunar Hebrew Calendar used by the figures in the story rather than the solar Julian calendar used by the Romans.

Any holiday that always takes place on the same day on a solar calendar is self-evidently not laid out in scripture as a holiday.

Maybe Ascention, but IDK anyone who actually celebrates that (like, what do you even do for it?). It is a national holiday in Sweden though, so we don't have work/school on it (which I obviously won't complain abouy), but other than that it is pretty much a regular day.

“Smother” isn’t really the right word IMO.

SOME times Christian customs were patterned in a way to make converting and assimilating non-Christians easier.

BUT

Other times it was basically the reverse.

Christians were not always the social majority after all.

So depending on the time frame, you’d have Christians assimilate to the society they were in, making their celebration fit within the larger social groups customs, so that they could fit in, or stay off the radar, or whatever else made it easier to practice their faith without drawing negative attention

Three Kings Day/Epiphany? Though that was probably just a rip off of something much cooler the Greeks were doing

Lupercalia, a fertility holiday, occurred February 15. There are some parallels to St. Valentine's day.

One of the bacchanalian drinking holidays was March 17th, which is Paddy's day.