Mind flayers (illithids) in Dungeons & Dragons do not have one single, fixed origin; different editions and supplements give slightly different answers, but most modern lore frames them as alien, psionic tyrants whose empire collapsed long ago and who likely came from outside the normal universe (often tied to the Far Realm).

Core D&D origins

  • In early D&D (mid‑1970s), mind flayers were introduced simply as super‑intelligent, tentacle‑faced brain‑eaters from deep underground, with almost no backstory beyond being a mysterious, evil aberration.
  • Later lore described them as having once ruled a vast interplanar empire that enslaved countless races, until their gith slaves rebelled and shattered their civilization; ever since, the illithids have been in decline, lurking in hidden colonies.

Time travelers and lost empire

  • One influential thread of lore suggests mind flayers actually originate in the distant future, fleeing the heat‑death of the universe by traveling back in time and rebuilding their empire in earlier ages.
  • This “time‑loop” style origin explains why they seem fragmented and half‑remember their own beginnings, and why their empire is described as both ancient and yet somehow still to come.

Far Realm and cosmic horror

  • From 4th edition onward, official material strongly connects mind flayers to the Far Realm, a dimension of madness and impossible geometry that lies outside the normal cosmology of the D&D multiverse.
  • In this version, they “came to the natural world from the Far Realm long ago,” bringing with them their alien biology, psionic powers, elder brains, and the horrific process of ceremorphosis (implanting tadpoles into humanoids to create new mind flayers).

How this ties into “where did they come from?”

When people ask “where did the mind flayer come from,” they are usually mixing a few levels of origin:

  • In‑universe (D &D lore):
    • They come from a fallen illithid empire that once spanned worlds and planes.
* Many modern sources point to an extra‑cosmic origin in the Far Realm, with some older or side‑lore hinting at a far‑future, time‑traveler origin.
  • Out‑of‑universe (real‑world creation) :
    • The monster first appeared in 1975 in an early TSR newsletter and OD&D supplements, created as a uniquely terrifying “brain‑eating” villain for the game, then expanded through adventures, Dragon Magazine articles, and later rulebooks.

Why they feel so familiar now

  • Modern games like Baldur’s Gate 3 and shows like Stranger Things have pushed mind flayers into the spotlight, but both are drawing on the same core D&D idea: a tentacled, psychic overlord that manipulates and consumes minds.
  • That’s why current forum and “latest news” discussions often describe them with Lovecraftian language—cosmic horror, alien intelligence, and a past (or future) that was never meant for mortals to fully understand.

TL;DR: In D&D lore, mind flayers come from a collapsed, brain‑eating empire whose true cradle is either a far‑future timeline or the Far Realm outside reality; in real life, they were invented as a horror monster for 1970s D&D and have grown into one of the game’s most iconic cosmic villains.

Information gathered from public forums or data available on the internet and portrayed here.