How Peggy Carter Shaped the Marvel Cinematic Universe

Every journey has an end, and when it comes to the Marvel Cinematic Universe's Infinity Saga, that end is here. Tomorrow, Avengers: Endgame officially opens in theaters and concludes the epic story a decade and 22 films in the making. Yet, with the end upon us, it's important to look back at how it all began -- and I don't mean 2008's Iron Man. I want to go back to one specific character to whom the world that is the MCU owes for, well, everything: Peggy Carter.

There are bigger heroes than Agent Peggy Carter in the MCU. Iron Man, Captain America, Captain Marvel, and even Nick Fury are all arguably bigger heroes than she is. But despite being a little lighter on the big-gun heroics, none of those characters would occupy their heroic place without Peggy. If Captain America or Iron Man are the heart of the MCU, Peggy's its very soul, because she fundamentally helped create it.

Peggy Carter's influence is made up of two primary components: a direct, tangible influence on some heroes as well as that of spiritual architect as well. Peggy has a direct connection to heavy-hitters such as Captain America, Tony Stark, and the Hulk as well as Scott Lang, who will be potentially hugely influential in Avengers: Endgame.

Peggy's work with the Strategic Scientific Reserve saw the transformation of Steve Rogers into Captain America both physically and functionally. Even with his incredible physical powers after receiving the Super Soldier serum, Steve was little more than a mascot until, with Peggy's support, he picked up his shield for a genuine solo mission in the field. Later, a lifetime after Captain America's World War 2 service and even after Peggy's death, she continued to influence the hero. When her niece Sharon Carter shared Peggy's advice -- to "plant yourself like a tree, look them in the eye and say 'no, you move'" in the face of those trying to stop you from doing what is right -- he took that to heart.

Peggy also had a hand in shaping Tony Stark's future as Iron Man by way of her friendship with his father, Howard Stark. Something more fleshed out during televisions' Agent Carter series, Peggy again served as a guiding and inspiring force. In Howard's case, she literally saves his life in the Agent Carter Season One finale, and by saving Howard Stark, Peggy's friendship quite literally ensures that Tony Stark will eventually be born to grow up and become Iron Man. With the Hulk, it's what Peggy didn't do that ultimately gave the Avengers their big green team member. When she destroyed the last remaining sample of Steve Roger's blood, she didn't just say goodbye to the man she loved -- a show of strength that allowed her to move on and, ultimately, help found S.H.I.E.L.D. She also prevented the Super Soldier serum from being synthesized from the sample. Years later, an attempt to recreate it while using gamma radiation turned Bruce Banner into the Hulk, in part because she didn't hand over that blood sample.

And as for Scott Lang? Peggy was still part of S.H.I.E.L.D. when Hank Pym quit the agency in the 1980s, and it was her decision to simply let him go with his research instead of detaining him at the urging of Head of Defense Mitchell Carson (a secret Hydra agent) that not only likely saved Hank's life, but allowed him to continue his research on his own, setting the table for Scott to, eventually, suit up as Ant-Man. It's just another moment where Peggy's quiet strength and refusal to back down from what she knew was right that built the soul of the MCU, giving the heroes a solid foundation of right over might -- even if might has certainly been helpful.

It's that foundation, that very structure begun the moment Peggy Carter first appeared on screen in Captain America: The First Avenger, that remains every time one of the heroes suits up. When Endgame arrives, it may be the Avengers coming together to correct Thanos' wrong, but the ghost of Peggy Carter will be standing right behind them. Without her, there might not only be fewer heroes to suit up, but those heroes might not have the determination to do whatever it takes to make things right. Peggy Carter is the reason the Earth's Mightiest Heroes are, well, the Earth's Mightiest Heroes.

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