Originally, the Titans (or Titanians) had no connection to the Eternals; the two groups were independently created based on Greek mythology. When the Eternals were made part of the mainstream Marvel canon, the Titans were retconned as a branch of the Eternal race.
At the dawn of the Eternal race, they were divided into two societies, one which remained on Earth, and one which fled into space. When the Earth Eternals conducted an experiment in cosmic energy which unleashed the full potential of their godlike powers, the Titanians were too far away to receive the full benefit, and therefore developed less degrees of power. This experiment turned the leader Kronos into an immaterial being; his sons, Zuras and A'Lars, both wished to become the next leader, but when Zuras was voted to lead, A'Lars left for Titan to avoid another conflict. He eventually became the leader of the Titan colony, and took the name Mentor.
Titan has been altered by the advanced technology and powers of its inhabitants; under the surface, an entire balanced artificial ecology supports a colony of several thousand Titans with varying degrees of superhuman powers and longevity. The system is maintained by ISAAC, an artificial intelligence with vast power and knowledge. The core of Titan has been replaced with a massive fusion power generator, which supplies artificial sunlight to an array of lush gardens seeded with plant life from Earth.
In the late 20th century, Titan was colonized by humans from Earth who were willing participants in experimental genetic adaptation. Over the next thousand years, the Titanians evolved into a race of highly accomplished telepaths. One of the most powerful and famous Titanians is Saturn Girl (Imra Ardeen), who became a founding member of the Legion of Super-Heroes. Other well-known Titanians are Saturn Queen and Esper Lass (both members of the Legion of Super-Villains) and Mentalla (who tried but failed to join the Legion of Super-Heroes and later joined the Fatal Five to avenge her rejection).
- In the 2000 AD universe of Judge Dredd, Titan is used as a penal colony for holding the solar system's most dangerous criminals. It was erroneously placed in orbit around Jupiter rather than Saturn, but this was later explained as being the result of a scientific experiment in teleportation.
- Titan was the setting of one issue of Mystery in Space, where it was known as the Scarecrow World.