As a member of the Green Lantern Corps in the latter part of the 30th Century, Vidar was sent to Earth to stop certain experiments that had the potential to reveal the secrets of the birth of the universe. Tantalised by the possibility of learning these secrets and gaining powers equal to those of his masters - the Guardians of the Universe - Vidar turned renegade.
Stopped in his tracks by the Legion of Super-Heroes, Vidar was turned over to the Guardians for justice. Years later, he returned to Earth under the guise of Universo, and used the power of super-hypnosis to try to conquer the planet. At one stage he even managed to have the Legion of Super-Heroes outlawed, and turned the populace of the world against them. Universo's attempts to conquer the Earth were only prevented by the Legion when they were aided by his son Rond Vidar. As a reward for his efforts, the Legion made Rond an honorary member.
Universo continued to plague the Legion over the years, once even taking over the government of Earth and outlawing the Legion.
When Universo joined Superboy Prime's Legion of Super-Villains he participated in an attack which killed his son, Rond Vidar. Universo tried to claim Rond's Green Lantern ring after Rond's death, but was unsuccessful.