I was reading 'Monster Hunter Alpha' (2011) by Larry Correia and there was a zombie that was able to function with temperatures well below freezing. I am not including details as spoilers. In this case the zombie was a hybrid, not your standard late night movie zombie.
I looked around and found How do zombies survive the winter? (Walking Dead) and the closed question Would survival in a zombie apocalypse be easier in a colder climate? but could not find anything else about active zombies below freezing, in any specific universe.
I suspect the hybrid nature in this novel was responsible for the activity, and I want to ask a different question about that, but first looking to see if there are any previous works by other authors with functional zombies at freezing temperatures.
All the zombies I have been exposed to fictional or historical have been warm weather undead.
What is the first work featuring functional zombies at freezing temperatures?