Yes of course! Well... I do anyway... I'm an all or nothing kinda guy and I'm so invested in this universe I have to watch everything... even Agents of S.H.I.E.L.D...
I was having a chin wag with my mate after seeing Age of Ultron for the 50billionth time and I was explaining everything coming up in the MCU and his face just dropped into an expression of pure exhaustion. And it got me thinking... Do I have to watch everything? Yes, everything's connected, but how connected? Could I cope with watching some of the MCU, but not others... I'm still going to watch EVERYTHING, but I'm thinking about people like my friend, who have some interest, but aren't that invested.
By the way, I'm not talking end-credit scenes or one shots. This is for the casual Marvel fans. Enjoy!
So, here I'm going to go through everything we've had from the MCU so far and see whether we can watch these things on their own or do we need the other films to back us up? As I said, I'm an all or nothing kinda guy... I NEED to watch everything, I need every easter egg and in an ideal world I need everyone to do the same... Otherwise, how else are people going to know how C-3PO got his golden body cover without watching the 2003 animated Clone Wars series?! I mean GET IT TOGETHER GUYS!
So first off...
The Iron Man Trilogy
Iron Man (2008)
This film does work as a solo film. As the first movie in the MCU you don't need any prior knowledge and (from memory) it doesn't have any significant foreshadowing of the universe to come.
Iron Man 2 (2010)
Okay, so obviously you kinda need to watch the first Iron Man to watch this and it does really push at planting the seeds for The Avengers in a big way, with the first appearance of Agent Coulson, Nick Fury and Black Widow. So, personally I don't feel you can watch this without wanting to watch The Avengers Assemble. But if you can deal with questions unanswered, you can stop here.
Iron Man 3 (2013)
Again, I wouldn't recommend watching this without Iron man, Iron Man 2 and The Avengers. Some would argue that this film is actually Iron Man 4 and The Avengers Assemble was Iron Man 3. One of the main sub themes does rely on you knowing what happened in The Avengers Assemble, but I guess you could let the references go over your head. I would ague that you should never watch this film. If you already have, I'm sorry. Unless you liked it then good for you! I wish I had your optimism.
The Incredible Hulk (2008)
No. You literally don't need to watch any other film before or after this one. I like this film, but it's so separate from everything else. You don't even need it to explain the Hulk's origins for The Avengers Assemble because it's explained in that film.
The Thor Films
This film does very much work as a stand alone film. But with it's introductions to Agent Coulson and Hawkeye it does leave you wanting more. Loki, the villain in this, does later become the villain in The Avengers Assemble, but you don't have to watch that after Thor.
Thor: The Dark World (2013)
Again, I think it's fairly obvious that you need to watch the first Thor film to watch this one. This one is set after The Avengers Assemble, but personally, I don't feel you need to watch that to understand this. There are many references to The Avengers Assemble, but I feel that you can let them go over your head. They're not necessary to understand the story for this. It does introduce the Aether which is an infinity stone that will play a part later on in the MCU.
The Captain America Films
Captain America: The First Avenger (2011)
Personally I feel that this film is a set up for The Avengers Assemble. Without an interest in the wider MCU I don't think you can watch this film as a stand alone film. It has Stark Industries, the beginning of S.H.I.E.L.D, Hydra and the Tesseract.
Captain America: The Winter Soldier (2014)
Again, you need to watch the first Captain America before this and although it's set after The Avengers Assemble, if you can get over all the easter eggs and references, you don't need to watch that to get what's going on in this. There are loads and loads of references and easter eggs for the hardcore fans, but you won't even notice them, nor even need to notice them if you're a casual viewer.
The Avengers Films
The Avengers Assemble (2012)
To follow the story line you could argue that you need to watch Iron Man 1 & 2, Thor and Captain America: The First Avenger before you watch this film, especially Thor and Captain America. But actually, this film really does work well as a stand alone film. There's enough explanation to understand all the characters, their origins and everything. This film works very well on its own and you can get away with just watching this and nothing else.
Avengers: Age of Ultron (2015)
Although this is the latest film that's been released, I would argue that you only need to watch The Avenger Assemble before this and nothing in between. The story pretty much continues after the first film. There is a scene that shows all of the infinity stones, not as a passing reference or an easter egg, but would leave a casual viewer really confused... This scene does plan seeds to future events but they're NOT important to the story of this film.
Guardians of the Galaxy (2014)
This film is literally set at the other side of the galaxy to the rest of the MCU. You don't need to watch anything prior to this and you don't need to watch anything after... yet.
The TV Series'
Agents of S.H.I.E.L.D. (2013–)
First of all... DO NOT WATCH THIS... It's terrible. I'm sucked in... I HAVE to watch this... If you're a fan of the films, you don't need to watch this at all... But I don't think you can watch this without watching the films, it links with everything... even Guardians of The Galaxy. This series is currently building up to The Inhumans which is a film that's due to be released in 2019, so I don't know if you have to have followed Agents of S.H.I.E.L.D for that. I imagine that you wouldn't have to...
Agent Carter (2015-)
Unfortunately this series hasn't been released in the UK and I've had to watch it via questionable means. I have only seen the first 2 episodes, but from what I've seen I only imagine that you need watch Captain America: The First Avenger to understand the characters and the premise.
You really don't need any prior knowledge for this at all. Daredevil works as a stand alone series. It does have references and easter eggs to the wider MCU, but they're unnoticeable to the casual viewer. The series is going to be leading up to and link with other Marvel Netflix series, so in the future it may not be so stand alone as it is now.
What about the future?
As far as we are aware EVERYTHING is leading up to Avengers: Infinity War so the casual viewer may get a little confused... But generally, the MCU is quite good at making their properties accessible to casual viewers. Everything links via easter eggs and references, but largely, they can be ignored. You can watch the Captain America series without having to watch the Iron Man series and so on. However, as movies are released the easter eggs are getting less and less subtle and leaving casual viewers more and more confused.
What I tend to forget as a nerd is that non-nerds don't overthink things as much as nerds do! We're the annoying ones that point out every single easter eggs in the movie... I was adamant that you had to watch Captain America: Winter Soldier to understand Avengers: Age Of Ultron even before seeing it!
I hope this article helps those casual viewers who feel like they have to watch everything to understand one movie, because you don't!