Galactus's History
Galactus is the sole survivor of the universe that existed prior to the current universe. Originally Galactus was a humanoid named Galan, who was born on the planet Taa, a paradise-like world whose civilization is said to have been the most advanced of any of the known universe of that time.
However, this universe was in its final stages of collapse. Originally, like all universes in the Marvel Comics continuum, this universe had been a "Cosmic Egg" ? a primal sphere of disorganized, dense, compact primordial matter. The sphere underwent a "Big Bang," an explosion that hurled the matter outwards, where much of it eventually condensed into stars and planets. This universe expanded in size for billions of years, and then contracted, undergoing a "crunch" over the following billions of years. All of the matter of that universe was plunging towards a central point, where it was collapsing into a new "Cosmic Egg."
Taa's civilization was one of the last still in existence. Lethal radiation caused by the "Big Crunch" this universe was experiencing was wiping out all life across the universe. Galan, a space explorer, was dispatched to travel through the cosmos to find a means of saving Taa, but he found none. The radiation eventually killed off all but a tiny fraction of the population of Taa. Knowing their deaths were inevitable, Galan proposed to the remaining survivors that they die gloriously by piloting one of their starships directly into the heart of the "Cosmic Egg." As the starship containing Galan and his fellow survivors approached the focal point of the Big Crunch, the heat and radiation killed all the passengers except Galan, who strangely found himself filled with new energy.
At the moment Galan's universe met its end, the Phoenix Force amassed the positive emotions of all living beings in the cosmos to preserve them from eternal damnation, enabling the Sentience of the Universe ? the previous universe's equivalent to Eternity ? to meet with Galan. Within the "Cosmic Egg" the Sentience of the Universe revealed itself to Galan and informed him that though they both would die in the final moments of the universe, they would both survive through a joint heir born into the next universe. The Sentience of the Universe merged itself with the mortal Galan and thus Galactus, the devourer of worlds, was conceived.
Eventually the "Cosmic Egg" underwent another "Big Bang," thus creating the current universe. Eternity and Death, the ethereal embodiments of the new universe, were created in this "Big Bang," and the newborn Galactus was simultaneously hurled outward in his recreated starship.
The nascent Galactus drifted in his starship for eons as life began to come into existence in the universe, including the races that would give rise to the Elders of the Universe. Eventually the nascent Galactus's starship was sighted by Ecce of the Watchers, an ancient species who possess vast psionic and energy manipulation powers who had undertaken to observe the events of the universe. Ecce drew the starship down to his planet to study it. There he learned that the being within it had power beyond comprehension and would eventually be forced to consume entire worlds to satiate his hunger for life-sustaining energy. Realizing the danger the nascent Galactus posed to the cosmos, this Watcher considered destroying the entity ? who was still vulnerable due to his metamorphic state ? but instead decided to abide by the Watchers' oath of non-interference, and let the nascent Galactus depart in his starship. Although over time the Watcher race has come to understand that Galactus is an intrinsic and necessary component to the natural order of the cosmos, Ecce has expressed guilt over his decision those billions of years ago and feels partially responsible for the destruction Galactus has caused since.
The nascent Galactus employed his vast power and created a suit of armor to help him regulate his raging internal energies. He then transformed the starship of Galan into a kind of incubation chamber, where Galactus spent thousands upon thousands of years evolving into his current form. Finally, the incubation ship drifted into orbit around the inhabited planet Archeopia. The Archeopians themselves did not disturb the strange ship, but years later a marauding space fleet, nearing Archeopia and thinking Galactus's ship to be a weapon, attacked it. Galactus, with his metamorphosis complete, emerged and with a gesture destroyed the invading fleet. Galactus, realizing his uncontrollable hunger for energy, turned his attention upon the energy-rich Archeopia below. Galactus immediately consumed the life energies of the Archeopia, only a small fleet of Archeopian ships managed to escape the planet in time. (The Archeopian race would later be fully exterminated by the living planet Ego).
Over the following millennia Galactus constructed for himself an immense home, the world-ship he calls Taa II, which engulfs the Archeopian solar system as a tribute to both his homeworld and to Archeopia, the first planet he ever consumed. For several billion years Galactus consumed only planets uninhabited by sentient lifeforms, Archeopia being the only exception, and centuries passed between his "feedings".
However, as ages passed, the intervals between feedings decreased considerably in length, and Galactus found himself needing to consume worlds inhabited by sentient races if he could find no other worlds possessing the energy he needs in time to sustain himself. Galactus has succeeded in suppressing his sympathy for intelligent beings who are similar in nature to the entity from which he was birthed, and, realizing himself to be a higher kind of being than they are due to his intrinsic role in the natural order, is willing to destroy their lives to continue his own. Moreover, he is aware that he is meant to one day give back to the universe infinitely more than he has ever taken from it.
At one point Galactus threatened to destroy the planet Zenn-La, home of a civilized, humanoid race. One of that world's inhabitants, Norrin Radd, persuaded Galactus to spare the planet by volunteering to become his "herald" and search out uninhabited worlds for him to consume. Galactus agreed, and transformed Norrin Radd into the Silver Surfer.
Eventually, however, Galactus grew determined to consume the energy-rich planet Earth. The Surfer rebelled as a result, and Reed Richards of the Fantastic Four thwarted Galactus by threatening to use an alien device called the Ultimate Nullifier on him, a weapon that could lay waste to the universe and kill even Galactus. Galactus was forced to vow to spare Earth in exchange for the Nullifier's return, and he punished the Surfer for his betrayal by erecting an undetectable energy barrier that prevented the Surfer from leaving Earth.
Eventually freeing himself from his pledge to Richards by defeating the nearly omnipotent Sphinx (who was further empowered by the secrets of the universe downloaded from the Living Computer of Xandar), Galactus returned several times to Earth to consume it, but was always narrowly thwarted. Meanwhile, he consumed numerous inhabited worlds throughout the known universe to sate his hunger, and was feared as a menace to all known star faring races. Galactus also took on a succession of new heralds.
During his last attempt to devour Earth, Galactus had gone so long without "feeding" that his energies were the lowest they had ever been and he was near death; thus a large number of Earth's superhuman defenders actually succeeded in defeating him in battle. Galactus lay dying, succumbing to his own hunger, but Reed Richards saved his life with the help of Thor's mystic hammer Mjolnir. The grateful Galactus pledged his friendship to Richards and sincerely gave his word never to attack Earth again. Galactus has steadfastly abided by this oath ever since. During this visit to Earth Galactus recruited his latest herald, Nova.
Galactus continues to prey upon other worlds, and recently he destroyed the Skrull throneworld, thereby plunging the Skrull Empire into chaos. There is an account of a far distant alternate future, in which man no longer exists on Earth, and Galactus, therefore no longer feeling bound by his oath, consumes it at last.
At some point afterward, Galactus was targeted by the alien organization called the Elders of the Universe, who believed his death would trigger a new Big Bang and recreate reality. In this new reality, the Elders believed they would become a race a Galacti, each with infinite cosmic power with which to endlessly pursue their special interests. His former herald, Silver Surfer, the Fantastic Four, Franklin Richards, and his herald Nova managed to upset the Elders' plans.
When Nova finally rebelled as his herald, Galactus created another in the alien Morg, who ultimately murdered Nova on his own volition. Morg in turn was defeated by the collection of his heralds, leaving Galactus alone again.
More recently, Galactus' appetite became such that he would only devour the life forces of sentient beings and leave the planets on which they lived intact. He began to consume more and more frequently, because unlike the life essences of the planets he normally feeds on the life forces of mortal beings offer him no sustenance; thus his addiction left him perpetually starving, weakened and demented. He created a new herald, Red Shift, to help him succeed in devouring all of the sentient life forces he came upon. He approached Earth once more, and had to be driven off by a large contingent of Earth's superheroes, and Red Shift was defeated by the Silver Surfer. Finally, the Silver Surfer agreed once more to become Galactus' herald and to search for planets with sentient life to consume. Almost immediately, the Silver Surfer led Galactus to the homeworld of the Shi'ar Empire, perhaps the most technologically advanced in the known universe, in hopes they would have the forces to repulse the weakened planet devourer. The Shi'ar quickly joined with other races and several of Earth's superheroes to battle Galactus. During the conflict, the Silver Surfer managed to turn Galactus' own energy-siphoning machines on Galactus himself, fatally weakening him. Galactus died, warning that the madness which had consumed him was a precursor to another greater horror. As he passed away, Galactus was converted to energy by his own planet-destroying machines, revealing his true form, that of a sentient star. As Reed Richards noted, his energy would radiate forever outward, so he could never again reform.
Galactus' "death" allowed the being known as Abraxas, the metaphysical embodiment of destruction and the antithesis of Eternity, to emerge from his imprisonment. He soon began to cut a swath of terror through various alternate realities, including the murder of parallel versions of Galactus. He used the decapitated head of one alternate reality Galactus to target and home in on the prime reality Earth and to plant a mole in his version of the Herald known as Nova. On Earth, Abraxas attacked Uatu the Watcher, left him comatose, and stole half of his signature medallion. Abraxas taunted the Fantastic Four with the inevitability of his coming, enticing the team to search for the Ultimate Nullifer, the clues to the location of which were scattered among alternate realities. Ultimately, the Four found the Nullifer when Abraxas suddenly appeared and stole it from them. Abraxas called forth an army of Novas to attack Earth, and the Fantastic Four held no hope of defeating him. Instead, Franklin Richards, the son of the Four members Mister Fantastic and the Invisible Woman, combined his Celestial-level cosmic powers with those of his sister Valeria and returned Galactus to his natural state and thus restored balance to Eternity, at the cost of forever burning out his powers. Galactus easily wrenched the Nullifer from Abraxas, but due to interference from the army of Novas the Nullifier fell to Reed Richards, who used the weapon to destroy the multiverse. The result served to re-create the multiverse in which Abraxas had never escaped, and since all that was had ended, all that is was realigned, it allowed Mister Fantastic to survive along with all those who died in Abraxas' reign of terror.
Annihilation
During Annihilus' ambition of "conquering" the universe, Galactus was vengefully attacked by the freed surviving Proemial Gods, "Tenebrous, of The Darkness Between" and "Aegis, Lady of All Sorrows", leaving him badly weakened and was, along with the Silver Surfer, captured by Thanos, who was responsible for bargaining the gods into fighting the World Devourer. Galactus and the Surfer were brought to Annhilus and were experimented upon as weapons in Annhilus' war. Galactus was used as a sort of cosmic weapon, capable of destroying whole planets, and his the Surfer's cosmic power were fueled as potential weapons for the Annihilation Wave. Eventually Annhilus' overall plan was to used Galactus as a 'bomb' capable of destroying every life-form in the universe and thus fulfilling his desire of being the only being in the known universe. However, Annhilus' plan was foiled by the efforts of Moondragon, Drax and the Silver Surfer as they successfully freed Galactus. After teleporting Moondragon and Drax to safety and in his rage, Galactus proceeds to unleash a massive, omnidirectional blast that later becomes known as the "Galactus event." Silver Surfer is sent ahead of the blast by Galactus to herald the imminent destruction, as the unleashed "Galactus obliteration perimeter" wipes out the majority of the Annihilation Wave, more than three star systems and even vaporizes a Watcher. Galactus' action ultimately stop the war and forcing the remaining warring parties to form a truce.
Post-Annihilation
Following the end of the Annihilation war, Galactus became hungrier than before and have requested his Heralds to find planetary substance to his hunger. It is revealed at some point in the early years of the creation of the universe that Galactus became involved in a civil war between the Proemial Gods. He slayed Diableri the leader of the opposing faction of gods who attempted to gain total control of the universe, and imprisons the remaining surviving gods in the Klyn. Angered and concerned of the freed Proemial Gods Aegis and Tenebrous, Galactus ordered the Silver Surfer in finding and defeating the gods once and for all. After the Surfer kills the gods by luring them into the Crunch, the all-destroying border of the universe, Galactus saved a heavily beaten and exhausted Surfer in which both of them honor their gratitude to each other, and the Surfer once again become a Herald to Galactus.
The Surfer led Galactus to the planet Sakaar where he destroyed the planet after easily defeating both Skaar and the Surfer who was being controlled by Skaar. He became addicted to the Old Power after devouring the planet and set out to find all the planets that possess the Old Power within them.
Nu World
The Surfer found the dead body of Galactus and informed his master. Galactus traveled to Reed and has taken him to the planet to question him about it.
