Okay, I know this sounds crazy, but it actually makes sense. Just hear me out.
There are many Game of Thrones theories out there, some more widely accepted than others, but this one might just be my favorite. The theory says that Hodor is somehow connected to The Great Other, the evil deity of ice and death in the faith of R'hllor. According to the faith, R'hllor (also known as the Lord of Light) is the good God and The Great Other is the evil one. Melisandre explains that "death is his domain, the dead his soldiers" and it is a widely accepted that the White Walkers are his minions.
So how does Hodor come in to the picture?
The first thing you need to know is that Hodor's name is actually not Hodor. It's Walder. Hodor is just a seemingly random word he started saying one day, and since he won't say anything else, people started calling him that. Nobody knows why he says it, and that is enough to creep me out.
The next thing you need to know, is that The Great Other also has a different name. A name we don't know, because it must not be spoken.
“His name may not be spoken. He is the God of Night and Terror, Jon Snow, and these shapes in the snow are his creatures.”
Of course this could just be a funny coincidence, they both have names that aren't spoken out loud. But there's more!
In case you're not familiar with Norse mythology, let me tell you the story about Balder and Hodr. They were two gods, and also twin brothers. Balder was loved by everyone, he was the god of light and purity. Sounds familiar? Balder is pretty much the Nordic equivalent of the Lord of Light. Hodr however, was merely a blind god, with not much going for him. One might say that Hodor is "blind" to the world around him, being a simpleton and such. So, back to the gods. One faithful day, Hodr was tricked by Loki which resulted in him involuntarily killing his brother. The god Loki was known to wear the skins of other animals. A skin changer making Hodr commit murder against his will.
Can you think of anyone else who involuntarily killed someone? That's right, Bran warged into Hodor and made him commit murder against his will.
Some unreliable sources on the internet claim that Hodr is the god of all things cold and dark. However, there is no evidence to support this claim anywhere in the viking sagas. Something that IS proved however, is that the name Hodr means "battle" or "warrior".
I know the Norse mythology is a long stretch, but it's an interesting theory nonetheless, and it wouldn't be the first time an author is inspired by mythology. One thing I also find suspicious, is what happens when Bran wargs into Hodor. When you warg into the body of an animal or person, you can feel the presence of their mind at the back of yours. When Bran wargs into Hodor, Hodor's mind goes somewhere Bran "can't reach". Is Hodor hiding something?
If this is true, what will happen?
If this insane theory turns out to be true, we could potentially be seeing a shocking turn of events in the upcoming seasons. Will there be an episode where Hodor reveals his true self, master of the White Walkers, and marches south to destroy the Seven Kingdoms? Or could Bran warg into him and control the White Walkers without them ever suspecting a thing? Will there be an epic battle between Hodor and Melisandre? Only time will tell!