Jack Kirby's Fourth World is a turn of phrase commonly attributed to a family of titles created in the 1970s by writer/illustrator Jack Kirby.
When Jack Kirby returned to working for DC Comics in the 1970s, he introduced what would become known as the Fourth World concept. He created a science-fiction based mythology revolving around ancient deities known as the New Gods. Similar to the gods of Earth lore, the New Gods were larger than life, possessing fantastic powers, which they used in a never-ending struggle between good and evil. The original Fourth World concept was intended as part of a finite epic saga, but for reasons that have never been satisfactorily explained, was never brought to its ultimate fruition.
The Fourth World has two twin planets, New Genesis and Apokolips. The two were once a single planet, Urgrund, but it was split after the time of the Old Gods, which ended with Ragnarok. New Genesis is a place that can only be described as heaven, populated by a peaceful, compassionate race of Gods and ruled benevolently by Highfather. Its mirror planet, Apokolips, rivals hell in despair and cruelty and is ruled by the Darkseid.
Several races inhabit the Fourth World but the dominant species is that of the New Gods, descendants of the Old Gods. They have evolved by being so near to The Source and so they see themselves as gods. They wield magnificent powers and have lived for centuries unknown to the general populace of Earth. To us they are giants, from ten feet to thousands of miles high. Their source of transportation that allows them to breach the dimensional rift is their Boom Tubes. When they die, their souls join the Source Wall, fortifying the barrier.
Notable Inhabitants of Apokolips:
Notable Inhabitants of New Genesis: