Wednesday Comics: Multiversal Spotlight: Earth-33

Earth-33
Concept: Earth-Prime
Pictured: Ultra and everybody
Sources/Inspirations: Flash #179, Flash #278, Justice League of America #123-124, Justice League of America #153, DC Comics Presents #87.
Analogs: Earth-Prime of the pre-Crisis universe, first appearing in Flash #179 (May 1968); post-52, Earth-Prime was home to Superboy-Prime and a version of the Legion of Superheroes as seen in Final Crisis: Legion of 3 Worlds #5 (July 2009)
Comments: Earth-Prime started out as the place where the stories of DC Comics were read and written. In Flash #179, the Flash winds up their and enlists the help of Julius Schwartz, then writer of his title, to return to Earth-One. Flash #228 introduced the wrinkle of the writers on Earth-Prime not just chronicling the adventures on the other earths but influencing them, as well. In Justice League of America #123 (1975), Cary Bates briefly becomes a megalomaniacal super-villain on Earth-Two thanks to this power. That would set the stage for tragedies to come.

In Justice League of America #153, Earth-Prime stops being our world when he gets its own superhero, Ultraa. Still, Ultraa decides Earth-Prime just isn't ready for superheroes and migrates to Earth-One. Even though Ultraa had a similar origin to Superman's, Earth-Prime gets its own Superman in the Crisis crossover DC Comics Presents #87 (1985) in the form of Superboy(-Prime).

Earth-Prime gets destroyed by the Anti-Monitor in Crisis and Superboy-Prime gets raptured to superhero out of continuity heaven with Earth-Two Superman and Alexander Luthor at the events end. The ending doesn't last, as he's back as a maniacal, genocidal villain in Infinite Crisis.