Bunnymund, through descriptions in the novels and on official works and websites (not sure if it was explicitly stated in the movie itself) is a pooka.
Now, many of us haven’t heard of a pooka before, but I suppose the majority presumed something like “Oh, a large bipedal rabbit creature. Okay, that’s cool.”
Cool, but wrong.
The pooka, literally Irish for goblin, (we’ll get back to that later) is a shapeshifting faerie of Irish/Celtic/Scottish etc etc mythology and folklore. In Scandinavia, the pooka is closer linked to “pook”, roughly a nature spirit. There’s a big split where definitions go from the dark malevolent trickster sort, to a fertility and nature faerie or spirit.
As said before, pookas are shapeshifters, one of the forms being a rabbit. It’s more of a lesser-used form, however. Nevertheless, it’s where the Easter Bunny came from. How a totally unrelated spirit got associated so strongly to a Christian holiday, I have no idea. I’ll let somebody else research that.
This is where things get interesting. Hold onto your ears.
A more common form of the malevolent pooka, found in Irish folklore is a black horse with yellow eyes.
Sound…

…familiar?
Haha, NO Amelia, that’s just a Visual Pun. Nightmare. Night Mare. Mare. Horse. Puns. Hahaha. Weesnaw.
No, I totally get that it is most likely played as that. I’m not done yet, though.
Remember how pooka is Irish for “goblin”?
Let’s look up some history of the Bogeyman, shall we?
The word could also be linked to many similar words in other European languages: bogle (Scots), boeman (Dutch), busemann (Norwegian), bøhmand (Danish), bòcan, púca, pooka or pookha (Irish), pwca, bwga or bwgan (Welsh), puki (Old Norse)
Wait, what was that?
pooka or pookha (Irish)
Bingo.
Literally Pooka-man.
And a bit more about the Pooka?
No faerie is more feared in Ireland than the pooka. This may be because it is always out and about after nightfall, creating harm and mischief, and because it can assume a variety of terrifying forms.
The guise in which it most often appears, however, is that of a sleek, dark horse with sulphurous yellow eyes and a long wild mane.
That definitely doesn’t sound like our Bunnymund, and more shockingly like our Nightmare King.
Some more information:
Parents often say that if their child is naughty, the bogeyman will get them, in an effort to make them behave.
I see. Irish mythology, what do you say?
Alternatively, the horse cults prevalent throughout the early Celtic world regarding the pooka may have provided the underlying motif for the nightmare steed.
Ah, nightmare steed. Just the phrase I was looking for. Thank you.
Basically, my point here is that Bunnymund and Pitch are…basically two drastically different versions of the same root mythology. I’m not claiming it’s canon within the RotG universe, but boy is it sure something to think about.
The way Pitch mirrors so many aspects of the other guardians is really interesting, and for me at least, this is the icing on the obscure mythology cake.
on a more hilarious note, would this make them like…cousins, in-universe? brothers, even? Step-brothers? Okay now I can’t unsee them being in the movie “Step Brothers” fUCK somebody draw them singing boats and hoes please do it i’ll love you forever
i mean
this is a serious informational post about mythology
yes

And therefore, Loki’s baby.
Daddy’s so proud.

In Norse mythology, Dökkálfar (Old Norse “Dark Elves”) and Ljósálfar (Old Norse “Light Elves”) are two contrasting types of elves; the prior dwell within the earth and are most swarthy, while the latter live in Álfheimr, located in heaven, and are “fairer than the sun to look at”