The show was the creation of comic writer Steve Gerber, creator of Marvel Comics' Howard the Duck. The name Ookla actually comes from UCLA, where Gerber's friend Marty Pasko went to college; Pasko invented the name.
Thundarr's weapon of choice, the Sunsword, projects a blade-like beam of energy when activated, and can be deactivated so that it is only a hilt. The Sunsword's energy blade can deflect other energy attacks as well as magical ones, can cut through nearly anything, and can disrupt magical spells and effects. The Sunsword is magically linked to Thundarr and as such, only he can use it; however, this link can be disrupted.
Comic book writer-artist Jack Kirby worked on the production design for the show. The main characters were designed by fellow comic book writer-artist Alex Toth. Toth, however, was unavailable to continue working on the show, so most of the wizards and other villains and secondary characters that appear on the show were designed by Kirby. He was brought onto the show at the recommendation of comic writer Steve Gerber and Mark Evanier.
Thundarr is voiced by Robert Ridgely. He is the main protagonist of the series. He is a barbarian that was once a slave to Sabian until he was freed by Princess Ariel and given the Sunsword which he uses as a weapon in his fight against evil wizards and other villains. Thundarr was frequently uttering such pronouncements as "Demon dogs!", "Lords of Light!", and the Thundarr war-cry "Aaaaahh-ee!". Thundarr, along with his friend Ookla, are largely unknowledgeable about the world and rely on Ariel's guidance, but Thundarr is respectful of knowledge gained. When once asked what kind of man he was, Thundarr simply replied "Free!"
On 28 September 2010, "Warner Archive" released "Thundarr the Barbarian: The Complete Series" on DVD in region 1 as part of their "Hanna-Barbera Classics Collection." This is a Manufacture-on-Demand (MOD) release, available exclusively through "Warner's" online store and Amazon.com. The DVD packaging mistakenly implies the series was made by "Hanna-Barbera" rather than "Ruby-Spears," even though that was not the case. On April 6, 2021, the series was released on Blu-ray by Warner Archive.