Elysium was a Class M world that hosted a Federation colony in the early 23rd century. It was named for the Elysian Fields of Earth's Greek mythology.

In 2228, terraformer Heston Prescott moved to Elysium, long with his wife Willa McKinnies and her son Christopher, to help Elysium better accommodate human habitation.

In 2231, a large wildfire swept across the colony, killing numerous colonists, including Prescott and McKinnies. Christopher survived and was taken back to Earth by his biological father, Charlie Pike.

The colony and its capital, Elysium City, recovered from the disaster. A second city was eventually built, and named in honor of Prescott. (TOS novel: Burning Dreams)