Angor is an example of a 'terra obscura' ... a parallel Earth in a single dimension and galaxy; in this case, Angor is a terra obscura for Earth-1 although it bears striking resemblances to Earth-616. As often happens, information passes between terra obscurae, and as a result, some of the heroes of Angor appear in comic books on Earth-1.
I have incorporated (sometimes awkwardly) characters from Earth-7 and Earth-8, as seen in Multiversity.
(thanks for additional research by Ola Hellsten and Jason Kirk)
1939
Barracuda, half-human/half-Atlantean, has first public case. [Freedom Fighters #7-9]
Fireball, an android capable of generating flame, has first public case. He soon adopts the human name James Nielsen and takes on a kid sidekick, the young mutant Sparky. [Freedom Fighters #7-9]
1941
The Americommando has first public case, and soon takes on a kid sidekick, Rusty. [Freedom Fighters #7-9]
1942
The Crusaders form as a team, comprising Americommando & Rusty, Fireball & Sparky, and the Barracuda. [Freedom Fighters #7-9]
1957
"Uncle" Mitch Wacky, a famous engineer, inventor, and cartoonist, constructs Wackeyland. [Justice League Europe #18]
1961
Frank 'Doc' Future forms the Future Family, comprising Ghost Girl, Golem, and Fireball II.
1962
Perry Porter has first public case as the Battlin' Bug/Glo-Worm. [Justice League Quarterly #3, Sandman #36, Doom Patrol #45]
A surgeon becomes the avatar of the storm god Wandjina, fighting crime under that name and possessing super-strength, flight and natural storm- and thunder powers. [Justice League of America Vol. 1 #87]
David Dibble is exposed to radiation and becomes the mindless Behemoth.
Jay Abrams, a mutant in a world of normals who had to live with the mental agony of growing to over twenty feet tall, fights crime under the name Massive Man. [Justice League Quarterly #3]
1963
Tin Man/Machinehead, despite having to wear a chest plate all the time to keep his heart alive, has first public case. [Justice League Quarterly #3]
Thomasina Hewitta Edwina Angel has first public case as T.H.E. Angel. [Justice League Quarterly #3]
The Bowman/Deadeye, a master archer yet a very insecure man who relies on his analyst for support, seeks to prove himself and is seduced by the Russian agent Red Dragon into becoming an opponent of Tin Man/Machinehead. [Justice League Europe #16]
The Zen Men, comprising Uni-beam/Uni-orb, Night Troller, the Rat, the Startler, Windrider, and others, form as a team to advocate for mutant rights under the leadership of Herr Doktor Skull. [Justice League Quarterly #3, Doom Patrol #45]
Captain Speed (Harry Christos, "the fastest man on two legs") and the Silver Sorceress (Laura Cynthia Christos, with the mutant ability of probability/luck manipulation, although she later becomes a gifted magician relying mostly on spells including flight, inter- dimensional travel, manipulation of matter, and telepathy) have conflicts with the Zen Men. [speculation, Justice League of America Vol. 1 #87]
1964
A movie stunt man injured and gifted with ultra-senses becomes Stuntmaster.
The Eagle, a war veteran whose family was slain by criminals, becomes a vigilante. He soon comes into conflict with Glo-Worm/Battlin' Bug. [Justice League Quarterly #3]
The Justifiers form as a team; Wandjina, Massive Man, and Tin Man/Machinehead act as mentors for the younger heroine T.H.E. Angel as well as the reformed Bowman/Deadeye and Captain Speed. This group even have their own English butler. [Justice League Quarterly #3]
The Americommando is revived by the Justifiers, having been in suspended animation since the 1940s. Disenchanted with his government, he adopts the name and costume of The Crusader. Over time he is accompanied by The Kite and Silver Eagle.
1965
The Justifiers break up due to internal tensions. Massive Man, Tin Man/Machinehead, and T.H.E. Angel leave the group (the latter eventually joining her fellow mutants the Zen Men). Wandjina, Bowman/Deadeye, and Captain Speed successfully reform Silver Sorceress; she joins the new team the Assemblers, and Harry Christos changes his name to Johnny Quick as a symbol of a final break from his villainous past (although he soon settles on the name Jack B. Quick in disgust after a visiting member of the Darkstar Corps informs him the name is already being used). [speculation, Justice League of America Vol. 1 #87]
1966
Herekles comes to Earth, establishing himself as a sometimes-friend/sometimes-competitor to Wandjina. [Justice League Quarterly #3]
Jay Abrams, realising his use of his mutant powers were endangering his health, manages to alter the effects of his mutant genes on his body, and rejoins the Assemblers as Blue Jay. In this new identity he can shrink to the size of 7", grow wings that give him the ability to fly, has increased speed, agility, and stamina. [speculation, Justice League of America Vol. 1 #87]
Fireball, having deactivated in the mid-50's, is revived by a villain who seeks to turn him against the Assemblers. Fireball soon realises the truth of the situation and becomes a member of the team in good standing. After a brief courtship, he marries Silver Sorceress, and the pair have a few happy years together before his tragic, final destruction. [speculation]
Mitch Wacky, after getting infected by the flu Ð a lethal disease on Angor Ð has himself put into a survival chamber. [Justice League Europe #18]
1967
Major Max, possibly an agent from Talok III, has first public case. At some point, he is replaced by a human woman who takes on the name.
Battlin' Bug/Glo-Worm has first encounter with the villainous Carny. [Justice League Europe #16]
1968
Jay Abrams creates an artificial intelligence which eventually becomes the heroic Microbot.
1969
Hyperius (and possibly others) is brought to Angor by an extra-dimensional force to battle the Assemblers. He later reforms and joins the team.
1970
Walküre has first public case.
1971
Ladybug has first public case. Despite her name, she has no connection to the Battlin' Bug/Glo-Worm.
Aliens from the planet Can-Nam-Loo sends robots to two worlds - Angor and Earth - to plunder their natural resources. [Justice League of America Vol. 1 #87]
A criminal gang are intent on stealing a nuclear device from the Timely Research Facility. During their reconnaissance mission, the device was accidentally detonated by a time-travelling Mitch Wacky and Silver Sorceress, with the men standing on Ground Zero. As so many times before on Angor, the result was not death, but mutation, their minds were damaged and their bodies endowed with powers on an extremely destructive level. Their leader's body grew so huge and disproportionate that only a specially designed techno-armor could contain it. He became the dreaded Lord Havoc. Erik Christos became the incredibly powerful master of magnetism, Doctor Diehard (it was he who took control of the nukes). A third, growing hideous tentacles from his head, called himself Gorgon, and a fourth became a savage, blood sensing animal with blades attached to his forearm and took the name Tracer. The last member of the group did not mutate. Instead, he was thrust into another dimension. When he returned to Angor, he was known as the Dreamslayer, a being of enormous psychic power with a possibly demonic origin. The Extremists were soon joined by the costumed villain known as Carny. [Justice League Quarterly #3]
These five beings became a greater threat than Angor had ever seen before. Apparently stopping at nothing, the Extremists recruited the rest of the world's super-villains and created an army of super-powered criminals. The heroes of the world stood powerless as the villains took control of the planet's nuclear arsenals, taking the entire world of Angor hostage and demanding that the world's leaders gave up their power in favor to the dictatorship of the Extremists. [Justice League Europe #16]
Blue Jay's technical skills uncover the fact that the cause of the explosion which mutated the Extremists was located on Earth. Mistakingly believing the Can-Nam-Loo robots (which the Assemblers soon defeated) to be Earth super-villains, Wandjina, Silver Sorceress, Jack B. Quick, and Blue Jay travel to Earth's space sector to enlist the assistance of EarthÕs heroes the Justice League of America to defeat the Extremists. Arriving first at Can-Nam-Loo en route, the heroes of each world mistakenly assume the others were the senders of the threats and promptly indulge in the ubiquitous hero versus hero battle. Peace eventually breaks out when Zatanna heals the injured Blue Jay. [Justice League of America Vol. 1 #87, Justice League Europe #16]
Upon their return, they were met with a horrible sight. Too late to help anyone, they realized that the planet's leaders had refused to give in to the Extremists, who then had made truth of their threats. Angor was completely ravaged by nuclear weapons. The cities lay in ruins. Most of the inhabitants were dead, including all their friends and seemingly the villains as well. As a last effort, the heroes attempted to be of some assistance to the few survivors, who were nonetheless mortally injured by radiation and continued to die one by one. Among the casualties was Harry Christos, whose hyperfast metabolism contracted cancer after exposing himself to the nuclear areas. [Justice League #2, Justice League Europe #16]
When there was no one left to help, the three remaining Assemblers, now calling themselves the Retaliators - Wandjina, Silver Sorceress, and Blue Jay - committed themselves to a new goal: They would prevent a disaster of this magnitude from ever happening, ever again, anywhere in the universe. From now on, the powerful trio travelled worlds and dimensions, visiting several planets and destroying their arsenals of mass-destructive weapons, no matter whether the planets' inhabitants liked it or not. [Justice League #2-3]
APPENDIX:
Americommando/American Crusader - Captain America
Barracuda - Sub-Mariner
Behemoth - Hulk
The Bowman/Deadeye - Hawkeye
Captain Speed/Johnny Quick/Jack B. Quick - Quicksilver
Carny - Kingpin + Arcade
Doc Future - Mr Fantastic
Doctor Diehard - Magneto
Dreamslayer - Dormammu
The Eagle - The Punisher
Fireball - Human Torch
Ghost Girl - Invisible Girl
Glo-Worm/Battlin' Bug - Spider-Man
The Golem - The Thing
Gorgon - Doctor Octopus
Herekles - Hercules
Hyperius - Hyperion
The Kite - The Falcon
Ladybug - Spider Woman
Lord Havoc - Doctor Doom
Microbot - Ultron / Scott Lang
Night Troller - Nightcrawler
Major Max - Captain Marvel
Massive Man/Blue Jay - Goliath/Yellowjacket
The Rat - Wolverine
Red Dragon - Black Widow
Rusty - Bucky
Silver Eagle - The Falcon
Silver Sorceress - Scarlet Witch
Sparky - Toro
The Startler - generic X-Men member
Stuntmaster - Daredevil
T.H.E. Angel - The Angel
Tin Man/Machinehead - Iron Man
Tracer - Sabretooth
Uni-beam / Uni-orb - Cyclops
Mitch Wacky - Walt Disney
Walküre - Valkyrie
Wandjina - Thor
Windrider - Storm