A brilliant scientist, Jor-El served Krypton's ruling council loyally for many years. At some point, he married Lara, the daughter of Sul-Van, and they had a son named Kal-El.
Sul-Van said once that Jor-El's primary flaw was his ego, that he was incapable of admitting that he could be wrong. Sul-Van may have been correct, but Jor-El never let concern for his reputation stand in the way of doing what he believed necessary.
Among his many accomplishments was thwarting High General Jax-Ur's attempted coup d'état. Discovering intelligence of the uprising, Jor-El gathered a small force of militia and captured one of the rebel parties, using their communications equipment to send out a signal that disabled the rest of Jax-Ur's forces. He did not deign to appear at Jax-Ur's trial, a decision Jax-Ur called cowardice.
Years later, Jax-Ur would call Jor-El "a clever man" with poor judgment in choosing sides.
Conducting research on a series of earthquakes rocking Krypton, Jor-El discovered evidence which he said predicted the planet's imminent destruction. His final five month expedition in the northern polar region only pointed to this outcome. Before sharing his findings with the Council, he prepared a rescue plan for the planet's population that required sending all of Krypton's populace into the Phantom Zone, allowing one person, traveling in a one-man spacecraft, to release them on a new planet. He planned for this destination to be Earth. His proposal was unanimously rejected, with some councilmen scoffing at the absurdity of having everyone take up residence among convicted criminals, no matter how temporary.
However, his findings were deliberately dismissed by the supercomputer Brainiac who the Council decided to believe. Still unwilling to admit that he might be mistaken, Jor-El investigated, and found that Brainiac had deliberately lied in order to give himself time to escape. By then, it was too late, as Krypton was to explode in a matter of hours. Jor-El could only put his backup plan into effect: to use his spacecraft to save his son, Kal. Programming the ship to carry Kal to Earth, Jor-El offered to send Lara with him. She refused, saying that her place was with her husband.
Before the ship departed, Jor-El and Lara recorded a message, telling their son that they loved him, and to always use his powers in a responsible way.
Jor-El watched the ship depart, and then kissed his wife as the world ended around them.
In Superman's fantasy world created by the Black Mercy where he grew up on a Krypton that never exploded and his family was still alive, Jor-El's warnings about the planet's destruction turned out to be wrong, and his reputation suffered a disastrous blow that took him years to recover from. In his later years, an elderly Jor-El was living by himself, but frequently visited by his son, daughter-in-law, and grandson.
- "The Last Son of Krypton, Part I"
- "The Last Son of Krypton, Part II"
- "The Last Son of Krypton, Part III" (Mentioned Only)
- "Stolen Memories"
- "Blasts From the Past, Part I" (Cameo as hologram)
- "Blasts From the Past, Part II" (Mentioned Only)
- "Bizarro's World" (Cameo as hologram)
- "The Call, Part II" (Cameo as statue)
- "Twilight, Part II" (Cameo as hologram)