Reign of the Supermen #168: Sonn the Star-Child

Source: Action Comics #370 (1968)
Type: The real deal (since retconned)So Superman's rocket went straight from Krypton directly to Earth (tiny detour aside), right? Well...

Action Comics #370 reveals that it actually entered a "space-warp", which sent it to another dimension for well around 100 years! A century in which Kal-El lived a whole other life! Ridiculous, you say? You don't know the meaning of the word.

So the rocket crashes on a planet in another dimension, one with properties very different from ours, which explains EVERYTHING. Kal is found and adopted by a kindly caveman couple, drawing only jealousy from his foster sister Ruda. By the time he's a grown boy, the society has somehow evolved to Antiquity. Kal - baptized Sonn by his new parents - never developed powers, but he nevertheless has the heroic instinct, such as when he defeats a rampaging "devil-dragon" that shoots "evil beams".
That's right. Not beams that are evil, but beams that MAKE YOU evil. Ruda will become his secret arch-nemesis. When they are adults, society's moved on and passed 20th-century technology and culture. Sonn is wearing a big S because the planet apparently uses the Latin alphabet, though no one else is silly enough to wear their initials, and his caveman father, now a scientist, discovers that society's leaps and bounds are caused by something Sonn radiates. It boosts their intelligence so much they feel the need to accelerate their fashions. This makes Ruda extra-mad, because despite all of her civilization's advances, she's still stuck in a dead end job as a telephone operator.
The discovery makes Sonn an overnight hero. He soon gets married to a girl whose name starts with L, and runs for president (and wins!).
Unfortunately, Ruda finds a way to distill the devil-dragon's "evil" energies and looses them on the world, dying herself from an evil overdose. Soon, the super-advanced people who remember living in caves cause a devastating nuclear war. They of course blame Sonn. His family is arrested, and he becomes a fugitive.
40 years later, he's a crazy old man living in the atomic wastes when his grown son finds him and brings him back to a lab. Vol, Son of Sonn, has built a rejuvenation booth. He'll put his father inside, regress him to an infant state, shoot him off the planet in his refurbished rocket and back into the space-warp from whence he came. As the rocket moves away, Sonn's influence on the world dissipates and everyone becomes a caveman again.
They did bomb themselves back into the stone age, after all! But wait, you say! What about all those stories where Jor-El peers at Earth and sees tractors and stuff? Well, it so happens that the other universe moves really fast compared to our own, so only a few minutes have passed. And though Superman has a mystery on his hands when he carbon dates his rocket, all that's left of that other life is a few vivid nightmares. He never found out the truth before it was Crisised out of him.