Iron Man’s creation of Ultron in Avengers: Age of Ultron played a key role in the MCU, but one theory suggests that the true creator was actually Thanos. While Thanos’ most memorable appearances were in the final two Avengers movies, he makes several smaller onscreen appearances before that. Before he is even shown on screen for the first time, events happened that were retroactively revealed to have been instigated by the Mad Titan.
After the invasion of the Chitauri in Scarlet Witch (Elizabeth Olsen), Tony Stark sets out on a mission to build a suit of armor around the world. While he and Bruce Banner (Mark Ruffalo) had dreamt of creating the Ultron AI as a form of protection for the world before, they had never been able to realize their dream. However, with the Mind Stone available to them, hidden in Loki’s scepter, they were able to create Ultron – but the consciousness quickly developed its own interpretation of the phrase “peace in our time.”
On the surface, it seems clear that Tony Stark's trauma led directly to the creation of the genocidal AI. However, there are breadcrumbs scattered throughout Avengers: Age of Ultron and the surrounding MCU that suggest that Ultron might actually have been part of Thanos’ original plan, with Iron Man playing only a small role in the eventual creation. It’s possible that this is reading too much into minor details, or that the elements are merely fragments left behind by Marvel as they slowly coalesced the MCU towards their final vision. However, here is why Thanos might really have created Ultron.
Why Iron Might Not Have Created Ultron
In Avengers: Age of Ultron, the Avengers reacquire Loki’s scepter containing the Mind Stone when they raid the base of the Hydra leader Wolfgang Von Strucker. Iron Man evaluates the work that Strucker was doing and sees that they were using the Mind Stone in their efforts of “knocking on a very particular door” in trying to create an artificial intelligence to power a robot army. Iron Man analyzes the Mind Stone and discovers a layout that appears to be a map of a computerized intelligence and suggests that Strucker was trying to recreate it.
While they attempt to create Ultron from this structure, they never actually succeed, giving up to go to a party as Jarvis runs some final tests. Afterwards Tony assures the rest of the Avengers that they “weren’t even close to an interface.” Even Jarvis first explains to Ultron when he wakes up that he is not sure why Ultron suddenly works. Like Strucker before them, Tony and Bruce had come close to creating Ultron but had failed in the final execution. This all suggests that an outside force had an additional hand in the creation, implying that Stark is not solely responsible for the destruction that follows.
Why Thanos Might Have Created Ultron
If Iron Man did not create Ultron, it therefore follows that someone else must have been involved. Thankfully, as the Mind Stone is one of the easier Infinity Stones to track through the MCU, it's possible to trace potential characters who may have been able to influence it. Before it came to Hydra by way of corruption within SHIELD, the scepter had belonged to Loki, and had been gifted to him by Thanos. Thanos had hoped that Loki would use the Infinity Stone to claim the Tesseract and return both to him. However, this plan never made a huge amount of sense, as giving up an Infinity Stone would be an odd choice for Thanos, much less handing it over to Loki, the being in the universe most likely to double-cross someone. His decision to hand the Mind Stone over to Loki for the conquest of Earth only really makes sense if Thanos had some sort of built-in failsafe in the form of Ultron.
Marvel has stated that the scepter exerted an influence over Loki, fueling his hatred of Thor and the people of Earth, which suggests that Thanos may have maintained some connection to the Mind Stone, or have tampered with it in some way previously. The theory that Thanos is behind the creation of Ultron suggests that he implanted something into the Mind Stone, either a program that would be able to subvert the intentions of someone tampering with it or, perhaps more plausibly, another entity entirely. When Ultron wakes up, he seems surprised to be in a digital form and expects to have a body. If he had not existed in some form before, there would have been no expectation of corporeal existence and Jarvis would not have had to educate him that he was simply a computer program. This is ed by the fact that Tony and Bruce evaluate the layout from the scepter and decide it looks like a mind, but not a human mind, suggesting that it could be the mind of a non-human entity, rather than simply an A.I.
Two final pieces of evidence come from the final moments of Avengers: Age of Ultron. During the wrap-up, Thor explains that he is going to have to look into the Infinity Stones as this is the fourth that has appeared recently and he feels that there is someone manipulating events behind the scenes, suggesting that Thanos’ plan might have extended to Ultron’s creation. Finally, during the Avengers: Age of Ultron mid-credits scene, Thanos is seen disappointedly saying “fine, I’ll do it myself.” While this could generally refer to Loki and Ronan’s failures, its placement at the end of Avengers: Age of Ultron suggests specifically that his frustration is aimed at the failure of events within the movie, implying that he had a hand in Ultron’s existence. If all of this is true, then Iron Man did not create Ultron: he just woke him up.
Why It Could Have Been Iron Man All Along
While there is strong evidence that Iron Man and Bruce Banner did not manage to create Ultron on their own, and additional evidence that Thanos might have been behind the A.I.’s creation, the case is certainly not straightforward. The Marvel Cinematic Universe is a complex beast that spans a huge amount of media, and its plan seems to have changed as it has progressed, meaning that some of these elements could be accidental. Therefore, despite the potential clues, there is still evidence that suggests that Thanos' influence may in fact be negligible.
For instance, while Thanos had access to a greater level of technology than humans, having easy access to space travel, it is not clear how he would have been able to tamper with the casing from the Mind Stone. Given that events in Avengers: Endgame make it clear that it takes all six Infinity Stones to produce the power needed to alter the objects (in the case of the final Phase 3 movie, destroy them), it's unclear how Thanos would have been able to fundamentally alter an Infinity Stone on his own. Since the Mind Stone is supposed to increase the intelligence of the wielder, having it in his possession may have made it easier for the titan to imbue it with consciousness. However, it remains a potential hole in this theory.
A final flaw with the Thanos origin theory was presented in What If…? as, when Thanos appears before Ultron holding five Infinity Stones, Ultron easily kills him, apparently taking him by surprise. While it would seem strange for Thanos to be surprised by Ultron if the AI was Thanos’ creation, What If…? downgraded Thanos’ threat level several times throughout the series, so it may purely be an inconsistency. Nevertheless, it still represents a problem for advocates of the idea that Thanos created Ultron. Ultimately, there is plenty of evidence to suggest that Iron Man really is responsible for creating Ultron in Avengers: Age of Ultron. However, it's also possible that Thanos might have been behind Ultron himself, posing serious implications for the popular interpretation of the MCU.
