Background

Earth D was an universe created by Marv Wolfman and Paul Ryan as part of a lost chapter of Crisis on Infinte Earths and than was published on Legends of the DC Universe: Crisis on Infinite Earths #1. Chronologically the story is set between chapters 4 and chapter 5 of the original Crisis on Infinite Earths and follows the efforts of the heroes of earth one to save an alternate reality, and failing at that.

It has been suggested than Earth D inspired later interpretations as in Earth-23.

History

Earth D was one of the many alternate worlds of the DC Multiverse than existed before the first crisis and resembled strongly to Earth-1, but with essential differences: The heroes of this world were all more racially and nationality diverse: a japanese Flash, a native american Green Arrow, an Indian Wonder Woman, a brazilian Green Lantern, a black Superman and Supergirl, and Middle Eastern Hawkman and Hawkgirl. Together, they are the Justice Alliance of America. Also the level of danger and the feeling of this Earth was lees dark and more close to the early Silver Age (fantastic no so lethal threats) than the later Bronze Age stage where Earth-1 was evolving, something The Flash of Earth-D comment on Flash of Earth-1 (Barry Allen).

When Barry Allen was trying to be captured by the Anti-Monitor he landed on Earth-D, an alternate earth which was starting to feel the effects of the incoming crisis. With the help of Barry Allen and heroes called from Earth-1, they repelled the first wave of shadow demons but their Superman died on that attack. The death of Superman was a bad omen, because on earth d he was the first superhero to fall in battle.

Understanding than they will be overcame by the oncoming crisis, the heroes of earth d worked to move the most of civil population to earth one using the cosmic treadmill technology to create a bridge to the other universe and save the most people possible. When the shadow demons attacked an second time and tried to destroy the technology, the heroes of earth d fought back to make sure the most people could escape and closed the bridge, to make a last stand against the forces of the Anti-Monitor and falling together in battle, as heroes.

Other versions

Arrowverse

After their initial appearance and death, Earth-D has been revisited in the crisis on Infinite earths giant, a comic special spin off of the adaptation of the original story in the live action crossover series of the Arrowverse. There Earth D is also victim of the attack of the Anti-Monitor and his shadow demons.

DCAU

Recently, in the Justice League Infinity, a revisitation book based on the DCAU, a new version of Earth-D appeared, with slight differences, including his Superman, who shows a strong influence of Calvin Ellis, from Earth-23. At difference than the original Earth-D, this version have darker shades in its story, including a civil war on Paradise Island than left Wonder Woman as their only survivor and a longer and more violent World War II, where it was Hermann Göring the leader of the Nazi party. Such conflict left such global trauma than a global government was stablished on Earth-D.