Today, Christmas cards feature the usual trees and sleighs and, if you're really lucky, a family photo in which every member manages to look their worst in different ways. Back in Victorian times, though, you could find yourself sifting lovingly through a stack of images of dead birds, murderous frogs, and scary old men:
Historians have looked into what the hell and offered various explanations on what this shit even is. They think the dead birds probably come from British folk tales that designated robins and wrens as "sacred species" and serve to remind recipients of the suffering of the less fortunate, but then what's with the smiling cake (? Ham?) with wine bottle legs?
It's important to remember that the iconography and traditions of Christmas as we know it are really recent. Even our image of Santa Claus only dates back to the 1800s. Victorian Christmas was a lot less about Jesus or even Santa and more about partying your dick off in case you didn't survive the winter, which was a lot less hypothetical than you'd like in those times.
These were the people who popularized seances and corpse photography, so they were pretty comfortable with the darker side of life, and Christmas cards also served a somewhat different purpose back then. Instead of chuckling for a half-second at a stupid reindeer pun and then throwing them into the recycling bin, Christmas cards were meant to be displayed all year, so it was really more of an art swap. Sending someone a Christmas card didn't say, "Hope you get a lot of gifts and ham," it said, "Look at this hilarious dead frog." That's right: Christmas cards were the original meme subreddit.