Black Widow comic published in 2009 has essentially defined the character for the MCU. Natasha Romanoff made her comic book debut in 1964, but frankly anyone who's only familiar with Scarlett Johansson's big-screen incarnation wouldn't recognize those first appearances. This was the height of the Cold War, and Stan Lee couldn't resist creating a sexy super-spy to cause problems for committed capitalist Tony Stark. In fact, this original Black Widow didn't even have a costume - because what spy wears the same outfit all the time?

Like many superheroes, Black Widow's backstory has been written and rewritten many times, and as a result over the decades it became incredibly complex. In 2009, Marvel Comics recognized that Iron Man 2 was going to put the comic book character back on the map, and as a result they recruited writer Paul Cornell to write a miniseries that would tie together all the tangled plot threads. The result was a miniseries called Black Widow: Deadly Origin.

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Paul Cornell's miniseries rewrote the history of the Red Room, revealing that they'd trained far more female super-spies than had previously been believed. What's more, where previous writers had considered Natasha Romanoff to be the only Red Room graduate to be called the "Black Widow," Cornell suggested that everyone who successfully completed training at the Red Room was referenced by that codename. Meanwhile, specific aspects of Red Room training were introduced in Cornell's run, including the idea that operatives were trained in ballet as a cover career for their international travel, and that the girls were sterilized at the end of their training.

Black Widow White Suit

All these elements were incorporated into the Marvel Cinematic Universe, with Joss Whedon drawing upon the ballet and sterilization in Avengers: Age of Ultron. The Black Widow trailer has made it clear that the MCU's Red Room has trained countless Black Widows, and even showed some flashbacks in which Natasha practiced her skills alongside other potential Widows.

Meanwhile, Black Widow: Deadly Origin featured two particularly important secondary characters. The first was Alexei Shostakov, a Russian cosmonaut who Natasha Romanoff became close to. She saw the opportunity of marrying in order to escape the Red Room, but unfortunately was unaware that the Soviet government had different plans for Shostakov. They had Natasha's husband fake his own death in order to participate in their own version of the super-soldier program, and he became the Red Guardian; Natasha consigned herself to her fate, and accepted her role as a Black Widow.

Alexei Shostakov in his Red Guardian costume in Black Widow

Appropriately enough, Red Guardian is due to make his MCU debut in Black Widow, where he'll be played by David Harbour. The second character was Ivan Petrovich Bezukhov, a father figure for Natasha who desired to be something far more. While there's been no indication he'll appear in the MCU at all, it's notable that in Avengers: Endgame the Red Skull demonstrated his knowledge by calling Black Widow "Natasha, daughter of Ivan." It seems that, in the MCU, Ivan Bezukhov really was Natasha's father.

Finally, Black Widow: Deadly Origin is also notable for the introduction of one final concept that's soon to be incorporated into the MCU; Natasha Romanoff's white costume, which she wore when she headed into a snowy environment. It was chosen for tactical reasons, because it's perfectly suited for espionage in a colder climate. And it seems to feature prominently in Black Widow, if the trailer is anything to go by - visually confirming the continuing impact Black Widow: Deadly Origin has on the MCU.

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