Tracy Chapman is a pretty trolly answer, but I suspect the real answer might very well be a musician or filmmaker, not a writer.
Walter Disney, obviously.
Well, it will probably take at least another century for the fact to hit.
Walt Disney is overwhelmingly about older stories (Cinderella, Snow White, Sleeping Beauty), and not anything I feel distinctly "American".
The most popular and timeless properties out of Disney (ex: Mickey Mouse) aren't really telling stories or setting cultural trends IMO. Meanwhile, Superman and Spiderman (Okay, I know Stan Lee only partially had influence on Spiderman...) are closer to what people see as distinctly "American".
Maybe Epic Rap Battles of History has the answer:
it's not like he had anything to do with superman
Seriously doubt it.
Both "how Americans see themselves and how people around the world sees them" was established way before both the MCU and before superhero comics became anything else than a preoccupation of the nerdy niche.
In the 60s, and 70s, and 80s, few fucks were given around the world for the Marvel comic universe (they still sold somewhat, just not that important culturally), and it was definitely not how people got to perceive the US: hollywood, the western, rock n' roll, all those were 100x more important. And Disney was way more important than Marvel at the time too.
Moana? Sleeping Beauty? Mickey Mouse?
The only major "American identity" film I can think of was Princess and the Frog. Maybe Big Hero 6 (at least the San Francisco half).
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The others are correct in that Mark Twain is probably the real answer. But I'm thinking of a modern media (film, comic books, etc. etc).
Maybe Wicked and Wizard of Oz counts as two sides of American culture. A push and counter push.
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Sleeping Beauty? That's French. Beauty and the Beast? Also French.
Great Mouse Detective? British. Alice in Wonderland? British.
Pinocchio? Italian.
All of them. None of those MCU movies really did anything to the "american psyche", forgettable entertainment.
And even if they had done, the question was "in terms of how Americans see themselves and how people around the world sees us". Nobody sees Americans in in 2026 the way Stan Lee or MCU saw them. Not even themselves. How they have been seen in general wasn't determined in 2026 or 2020 or 2000, but in the 20th century. And even how they're seen and see themselves in 2026 is not defined by the MCU either.
Concerning the general view on US, Disney movies (especially including Pixar) have had much more influence. But I mentioned other even more important things: Hollywood in general (pre-MCU, from early film to John Ford, and to Copolla and Scorsese), the western and the idea of the west/'frontier', rock n' roll...
>Sleeping Beauty? That's French. Beauty and the Beast? Also French. Great Mouse Detective? British. Alice in Wonderland? British. Pinocchio? Italian.
In their Disney treatment they're 100% American.
Yes, Sleeping Beauty, et al were originally from "not the US" countries, very few people outside those countries remembers that. Instead, they're Disney, or at least US.
Basil of Baker Street (Great Mouse Detective) literally saves the Queen of England.
Robin Hood and The Sword in the Stone are also similarly very, very British. No one can possibly confuse the issue.
But yeah, Jack Kirby would be closer than the other two.
I'd also suggest that cultural impact plays a strong part in Homer's prominence. The American Homer would probably be older rather than more recent (at least by present reckoning).
Francis Ford Coppola / Mario Puzo, The Godfather; Michael Curtiz, Casablanca; Steven Speilberg; Orson Welles, Citizen Kane; Richard Rodgers and Oscar Hammerstein, Oklahoma!, South Pacific, The Sound of Music, etc., might make my list.
Questioning authority and mythology is very American.
Kubrick made all his iconic movies (except Spartacus and Paths of Glory) while settled in Britain, and shot most of them in British studios.
Wheres the evidence that Homer work ed for the mythology of Dark Age Greece?
If you say its his popularity..
(I would cite the Cyclics as counter evidence)
For filmmaker: itd have to be someone whom you can imagine (unironically) reconstructing Adams or other actual American heroes
So..
Tom Hanks
Although most popular knowledge about him revolves around his earlier acting career (Westerns, Dirty Harry), you'll notice a distinct change in many of his films once he started directing.
* Play Misty for Me
* Breezy
* Unforgiven
* A Perfect World
* The Bridges of Madison County
* Midnight in the Garden of Good and Evil
* Mystic River
* Million Dollar Baby
* Changeling
* Gran Torino
* American Sniper
* Sully
* The Mule
But he has also been an OST composer for some films.
But as a director, they could be elevated to the status of creator, and perhaps directing is the truer American art form rather than ...epic poetry or the novel. Which speaks to the core of the question at a different level.
Besides, Homer didn't write his own plots either, he adapted original screenplays, so to speak!
Letters from Iwo Jima
Flags of our Fathers.
He certainly took me by surprise by the depth of his offerings, given that I used to know him as blondie with no name and for dirty harry.
Recency bias? Why not Jimmy Stewart? Gregory Peck? Humphrey Bogart? Paul Newman, Robert Redford?
https://en.wikipedia.org/wiki/John_Adams_(miniseries)
And will be playing and producing Dodd.
https://variety.com/2019/film/news/joe-wright-in-the-garden-...
Theme of his oevre is not-so-immortal American heroes and heroism through and through
Except for Redford, the others don't have their own voice
Edit: but Tom Hanks is really only barely getting by from Hollywood getting less repressive over time