Warning: This article contains SPOILERS for Doctor Strange 2 and What If...? Episode 1.
Though Steve Rogers is Captain America in the Marvel Cinematic Universe, there's a reason Doctor Strange 2 as a part of the Illuminati.
In the What If...? premiere, Peggy Carter finally gets her due. After Carter chooses to watch Steve Rogers' (voiced by Josh Keaton) transformation into a super-soldier from the floor instead of the safety of a booth, the events of Captain Carter as they do in What If...?.
After taking over as a super-soldier, Carter makes a notable change to her name. In the What If..? premiere, Carter takes the war effort into her own hands and uses the moniker of Captain Carter. With Rogers known as Captain America, it'd make sense for Carter, who's British, to become the MCU's Captain Britain. After all, there's already a character known as Captain Britain in Marvel's comics, so it'd be an easy transition to use that name in the MCU. However, there are a few different reasons that Carter does the name change.
How Captain Carter Is Stronger Than Captain America
The name Captain Carter is a way to honor the character. Though she was an integral part of the MCU and Agent Carter, was unceremoniously canceled after two seasons. The cancellation left numerous unanswered questions about Carter's backstory and a sour taste in peoples' mouths. The Captain Carter name is a way to give the nod to the character's importance and the impact that she's had on the MCU.
Captain Carter Vs. Captain Britain: The Differences Explained
Despite similar costumes, there are major notable differences between Captain Carter and Captain Britain. The first is their origins. The first Captain Britain was originally Brian Braddock, a scientist who is granted his powers through Merlyn and his daughter. The second is Kelsey Leigh, a single mother who sacrifices herself to save Captain America. Kelsey is the one who trades in the original Captain Britain's amulet for a sword, as it's more useful in battle. Captain Carter was created in a lab, basically, as Captain America was. Therefore, the origins of their powers are wholly different. One comes from magic, and the other comes from science.
Another way they differ is their powers, which does fall under their origins. Since Captain Britain's powers are more magical in their foundation, Kelsey and Brian should be considered an entirely different type of hero than Peggy Carter's Captain Carter. The Cap is designed to be the perfect supersoldier, whereas Captain Britain gains their powers from a multiversal magical being. While markedly dissimilar, Captain Carter and Captain Britain have a bit of continuity. Both heroes were designed to protect their patriotic land, and like Kelsey, Peggy Carter does wield a sword in both What If...? and Doctor Strange 2.
Additionally, Captain Carter is true to herself. Though there's a Captain Britain in Marvel Comics, it doesn't have much to do with Carter. And there's no reason Carter should have to give up her title in the name of patriotism. In an interview (via Polygon), What If...? head writer A.C. Bradley noted that Carter doesn't hide behind a mask, so the character has no reason to hide her real name. The name Captain Carter in Marvel's What If...? and Doctor Strange 2 celebrates Peggy Carter, and there's no need for Marvel to mask that.
Marvel's What If...? releases new episodes Wednesdays on Disney+.
