Good King Whatshisface
I have always found Good King Wenceslas
This is a real guy, although he was the Duke of Bohemia, and not a king, he was a real member of the 10th
century aristocracy, and he is the patron saint of the Czech Republic. He is revered as a kind man for the way he treated children and slaves. Apparently owning slaves is fine as long as you don't kill too many.
His mother had his grandmother, her mother-in-law, strangled, and he forced his mother out at sword point. He sounds more like he was ready for Dr. Phil, than canonization.
So then we get to the song. The song says that on Saint Stephan's Day, the day after Christmas, he sees one of his peasants out scrounging up fallen limbs to heat his humble hovel, and Wenceslas carries food and a few logs to the peasant's abode to brighten up the holiday.
At the time commoners weren't allowed to cut trees for firewood nor hunt, as those were the rights of the aristocracy. They were allowed to pick up dead limbs in the forest to heat their homes. They would have a fire in their shacks and a smoke hole in the roof, not a fireplace, so the logs weren't going to be useful unless they were split.
On the day after Christmas there were sure to be a lot of leftovers that would go to the kennels, so the "Good King" Wenceslas was carting dog food to a peasant, who was expected to be overcome with gratitude at the beneficence of his Duke.
There is a happy ending: Wenceslas was murdered by his brother's goons after five years of showering the peasants with the happy life that had them out seeking firewood in the middle of a blizzard.
The Church felt kindly towards Wenceslas because his mother was rather repressive towards the Church, while he wasn't, so he became a martyr.