How could Asgard return in God of Thunder and a small number of Asgardian refugees could only watch as Asgard was destroyed by the power of Surtur, sacrificed in order to defeat Hela.
Tragedy stalked the Asgardian refugees. As seen in Avengers: Infinity War, Loki took the Tesseract from Asgard before its destruction, and in doing so he caught the attention of Thanos. The Mad Titan cut down half the survivors, killing half of them as he continued his insane mission to rebalance the universe. Then, when he acquired the Infinity Gauntlet, he snapped his fingers, erasing half the living creatures in the universe. The Asgardian refugees were reduced in number once again, and - haunted and broken by their experiences - they settled on Earth. They established New Asgard in the Norwegian town of Tønsberg.
And yet, for all the Realm may have come to an end, set photos from Thor 4 suggest Asgard will return. Aerial shots taken while the sets were being created showed some very familiar structures, suggesting the story of Asgard - the place, not the people - is not yet over.
Thor: Ragnarok Changed Asgard's Role In The MCU
When Marvel first took viewers to Asgard in Thor's magic was hand-waved as advanced science, with the movie literally calling out Arthur C. Clarke's famous maxim that any sufficiently advanced science would look like magic.
Marvel became increasingly bold over the next few years, though, with hints of actual sorcery and magic in Thor: Ragnarok, which completely redefined the Asgardians and their home. No longer were the Asgardians aliens who had been viewed as gods; now they identified as gods themselves, and their powers were drawn from their own natures. This had the impact of transforming Asgard as well; now, Asgard was great simply because it was the home of the gods. This, ultimately, was why Thor chose to destroy the Realm Eternal by ushering in Ragnarok; he had realized that, so long as the people of Asgard remained, Asgard would never truly die.
This Ushers In The Legends Of Ragnarok
By embracing the idea the Asgardians are actually gods, Marvel Studios has - perhaps unintentionally - pointed towards a mythical interpretation of the events of Ragnarok, which is all about a new Ragnarok cycle beginning in the twenty-first century. And it has been implicitly absorbed into the MCU as well, simply by Marvel's decision to acknowledge the Asgardians as the genuine Norse gods.
The comics have tapped into this rich vein of mythology, and there have been several Ragnarok arcs there. In the comics, Odin had given Thor an experience of mortality that meant he was as human as he was divine, and this granted him the unique perspective to recognize the cycle of death and rebirth. He ultimately broke it - allowing all Asgard to be destroyed, ushering in what he believed was the death of his people. But he had been wrong, because he had failed to understand what it means to be divine. Thor - and subsequently Asgard itself - returned in J. Michael Straczynski's classic Thor run in 2007, and these comics point the way to how Asgard could be restored in the MCU as well.
How The MCU Could Bring Back Asgard With Thor 4
Straczynski's Thor run revealed the gods and humans exist in a sort of loop, with the gods empowered by the faith and memories of mortals. "If it is for mortals to say whether gods exist," Thor was advised by a wise counselor in the afterlife, "then I say that they live on, in the hearts and souls and minds of mortals. They need only be found, and awakened." This proved to be true, for Thor found himself effectively reversing Ragnarok. First Mjolnir came plummeting to Earth, then the God of Thunder himself returned; and where there is Thor, there is Asgard, and soon the Realm Eternal was restored - albeit hovering over the surface of the Earth this time. Soon Thor had found the counsel he received was true, for his presence was able to discover the divine hidden within the hearts and souls and minds of mortal men and women, restoring the gods who had died during Ragnarok.
This idea of the interdependence of gods and men is a common one in fantasy books and TV shows, and it would be easy to incorporate it into the MCU as well. This may explain why Mjolnir is returning in Thor 4, ushering in the new beginning of the gods as it did in Straczynski's story, and it would even fit with Jane Foster's becoming the new Thor. After all, which other mortal has a greater knowledge of Thor and the gods, having walked the halls of Asgard and met Odin the All-Father himself? Those memories and experiences could be the key to recreating the gods.
But Jane Foster isn't the only one to factor in here. Norse gods are being told, inspiring faith and devotion. This could easily serve as further creative power to restore Asgard on Earth, just as in the comics - and so the cycle would begin anew in the MCU, but closer to Earth than ever before, with even a new Thor serving as champion of Asgard.
