The day before filming a fight scene with Robert Downey Jr., Sebastian Stan sent him a video of himself doing intense bicep curls in front of the decapitated head of an Iron Man suit. He attached the message, "Looking forward to our scene tomorrow Robert".
T'Challa had a much smaller role in the earlier drafts and did not even appear in costume, as the writers intended to put more focus on Spider-Man, and save Black Panther's origin for his own movie. However, when it looked like Marvel would not be getting permission to use Spider-Man, Black Panther's role was beefed up significantly. By the time they did get to use Spider-Man, T'Challa had already become so integral to the plot, that they decided to leave his role as it was, and give Spider-Man a smaller part.
Tom Holland commented on how intimidated he was when he came to screentest for Spider-Man, saying that Robert Downey Jr. took him aside and said, "Listen, I remember my screentest for Iron Man. I remember how terrified I was. Just think of it as an audition. It's nothing too scary. If you get it wrong, we'll just start again. No pressure."
(At around one hour and nineteen minutes) Tony Stark (Robert Downey Jr.) remarks how attractive Aunt May (Marisa Tomei) is. Downey and Tomei had a relationship in the 1990s, and appeared in two other films together: Chaplin (1992) and Only You (1994).
(At around one hour and thirty-five minutes) One scene shows Ant-Man (Paul Rudd) being boosted by an arrow from Hawkeye (Jeremy Renner). This is taken directly from the comics, specifically The Avengers #223.
(At around one hour and nineteen minutes) Co-Director Joe Russo said that "The most powerful shot of the film" was Steve Rogers stopping a helicopter from taking off, with his bare hands. The shot was featured in the first teaser trailer for this movie. Russo said Chris Evans worked very hard in the gym to physically embody the character, because they wanted to test the limits of Steve's physical strength. About the shot itself, he noted, "On-set, we had Chris straining against a crane, holding the helicopter to get this fantastic shot of his muscles bulging, and you can feel the energy and determination as he tries to stop it."
This movie revealed that Bucky Barnes had been hiding out in Bucharest, which is the capital of Romania. Sebastian Stan (Bucky) is a Romanian-American actor, who was born in Constanta, Romania, and raised there until he was eight. In the first scene set in Bucharest, Bucky is buying fruits from a street market. Stan's native language is Romanian, and therefore spoke it perfectly.
Spider-Man was very nearly removed from the film, as Sony Pictures originally rejected Marvel's proposal to allow them a cut of the profit if they could pull Spider-Man over, but Sony Corporation expressed disappointment in the financial returns and the critical reception of The Amazing Spider-Man series and decided to negotiate a deal again.
Screenwriters Christopher Markus and Stephen McFeely's original idea for this movie was a vastly different and much smaller film without the other Avengers, but Producer Kevin Feige suggested they adapt Civil War instead. Certain parts of their original idea still made into the movie, such as the emphasis on Steve and Bucky's relationship, as well as the use of Baron Zemo as the villain.
Chadwick Boseman (T'Challa, a.k.a. Black Panther) underwent a vigorous training program to get in fighting shape for the character. While admittedly not a big reader of comics as a kid, Boseman read as many comics as possible for anything Black Panther-related. Boseman also recycled the Xhosa accent he learned for Message from the King (2016), for the character.
Samuel L. Jackson was "surprised" to discover that Nick Fury would not be in the film after "the Russo Brothers told him he was." Executive Producer Nate Moore stated that Fury was not included "because he didn't add anything to the Civil War story they were telling."
Robert Downey Jr. acted as the younger Tony Stark, along with John Slattery and Hope Davis. Lola FX provided the "de-aging" visual effects on the face and hair of Downey with footage and photos of his early career as references.
Robert Downey Jr. and Chris Evans described the dynamic between Tony Stark, a.k.a. Iron Man, and Steve Rogers, a.k.a. Captain America, as a marriage, saying, "We love each other, but it's explosive. You're working toward the same goal, but you have very different approaches to it. It's blurry, and that's what makes it great. No one's right, no one's wrong. It's going to make it even harder for them to come to an agreement."
The appearance of Giant-Man was kept secret throughout production and marketing, evident from the absence of said character in all trailers and television ads, but this movie's Funko Pop! figurines, and a Lego set, depicting the airport battle scene featured Giant-Man, was released and advertised before the movie's release date.
Tom Hiddleston confessed that even though he did not appear in the film, it contained one of his favorite moments in the Marvel Cinematic Universe, the helicopter scene. He enthused, "I mean Chris Evans does a bicep curl, with a helicopter! If you don't love that, we can't be friends."
(At around one hour and nine minutes) Chris Evans injured his arm muscles while filming the iconic shot of Captain America holding back a helicopter with his hands. Evans said, "That shot is a little bit of bicep porn. 'Zoom in on the biceps', that's what the script said. Kevin Feige didn't airbrush my biceps, that's me. It's not a utilitarian shot, it's a shot where you're trying to look heroic. That position (of holding the helicopter with one hand and the ledge with another) is actually a very unnatural position to use to stop something, but we used it because I have to flex my bicep, you are trying to make the scene look great, and I genuinely messed my arm up doing that shot because of the strain." Robert Downey Jr. joked that the filmmakers didn't mind that Evans hurt himself because of how great the shot turned out, and they have been using it to promote the film ever since. Anthony Russo revealed that the iconic shot almost did not happen because on the day of the filming, there was a miscommunication with the Costume Department and Evans came in wearing a thick jacket. They immediately sent him back to change, because then they wouldn't have been able to film the shot of his muscles bulging as intended in the script.
The film was going to feature The Incredible Hulk, but he was shifted to Thor: Ragnarok (2017), and so the filmmakers chose Secretary of State Thaddeus E. "Thunderbolt" Ross (William Hurt) in the film, as a substitute to illustrate the theme of destructive power: "We thought it would be interesting to use a character who had a fanatical anti-superhero point of view, built on experience. He's cornering The Avengers politically now, he's out-maneuvering them."
Marvel initially wanted to hire Robert Downey Jr. to reprise Tony Stark as a small role, with just three weeks of work. However, Downey wanted a larger role, which would lead to a bigger payday. Marvel Entertainment CEO Ike Perlmutter was furious over the request, prompting him to order the screenwriters to write Tony Stark out of the script completely. When the deal seemed like it was off the table, Marvel Studios President Kevin Feige pushed to hire Downey, citing that his casting in the film could leave the door open for sequels, new franchises, and dramatic possibilities within the Marvel Cinematic Universe, as this movie could drive future storylines for these films. As a result with Downey's casting, the actor received a substantial payout that included a back-end participation deal, and another payout if the film's box-office gross succeeded Captain America: The Winter Soldier (2014), which it did.
In all three Captain America films, Bucky falling into a body of water represents a major change to the character. In Captain America: The Winter Soldier (2014), falling into the Potomac marks the beginning of his recovery. In this movie, falling into the river in Germany makes him realize the brainwashing still affects him. He also falls into a river during his "death scene" in Captain America: The First Avenger (2011), which marks his transformation into an assassin, but this is not revealed until the second film.
The filmmakers describe Bucky Barnes as a divided character, saying, "He's not Bucky Barnes anymore, he's not the Winter Soldier anymore. He's something in-between. There's a part of his personality that was under mind control, and he murdered a lot of people. So he has a very complicated history. Who is that person? How does that character move forward?"
Costume Designer Judianna Makovsky revealed that for all of Chris Evans' scenes, where he is in regular outfits (outside the suit), they purposefully made him wear t-shirts, which are many sizes smaller than his actual size, so that his muscles pop on camera. Evans said all of his t-shirt scenes are scheduled at the start of the filming, because he loses a lot of weight over the months it takes to film a Marvel movie. He said, especially, that filming the action scenes wearing the Captain America suit, makes him lose a lot of his size.
During the airport fight scene, a truck has the Bluth family logo. It is the same "stair car" (portable staircase for an airplane) that was the subject of many running jokes on Arrested Development (2003). The Russo Brothers, the directors of this movie, also directed the pilot, and many other episodes of Arrested Development (2003).
(At around one hour and fifty-five minutes) When Steve and Bucky remember going on a double date in Brooklyn when they were younger, Cap mentions Bucky's date was a redhead named Dolores, with the nickname "Dot". That description fits with one of Peggy Carter's nemeses from Agent Carter (2015), Dottie Underwood, also exploited as a weapon by the Soviets.
Hope van Dyne was going to become The Wasp in an earlier draft of the script, but she was removed, due to concerns that reducing her role to a cameo alongside the other characters would be a disservice to her as a character. The fact that Evangeline Lilly was pregnant at the time also probably influenced the decision. Producer Kevin Feige has asserted that she will officially take on The Wasp mantle in a substantial role at a later point in Phase 3, in Ant-Man and the Wasp (2018).
Tom Holland made audition tapes together with Jon Bernthal while filming Pilgrimage (2017), with Holland landing the role of Peter Parker, a.k.a. Spider-Man, and Bernthal the role of Frank Castle, a.k.a. The Punisher, in Daredevil (2015).
Chris Evans refuted claims that his biceps were CGI enhanced for the film's famous helicopter shot. He instead prepped a lot in lieu of artificial enhancement saying, "That was really my arm, and you know what, I took a page of Anthony Mackie's book. When we were doing Avengers: Age of Ultron (2015), for certain scenes, I worked out just before the take, but there were a bunch of scenes where I was the only one out of the cast doing it, and I'd be embarrassed, and feel shame. So I didn't do it that often, and then we started Civil War, and Mackie has no shame. Before each take, Mackie's just curling weights non-stop and I thought, 'Yeah! What are you doing Chris? Just curl some weights! Who cares? I am not going to worry about twenty people judging me, as opposed to two hundred million people seeing the scene forever.' So before the helicopter scene, I lifted a lot of weights to get pumped. It's not like I woke up and I looked like that, that was me lifting weight for hours on end prior to filming that scene. There certainly was a lot of pressure. I was fully aware of what they wanted that shot to be. I wanted that shot to be great too."
(At around thirty-three minutes) The speech which Sharon Carter makes at Peggy's funeral, is taken from a speech which Captain America made in Amazing Spider-Man #537 - "Doesn't matter what the press says. Doesn't matter what the politicians or the mobs say. Doesn't matter if the whole country decides that something wrong is something right. This nation was founded on one principle above all else: the requirement that we stand up for what we believe, no matter the odds or the consequences. When the mob and the press and the whole world tell you to move, your job is to plant yourself like a tree beside the river of truth, and tell the whole world - No, you move."
(At around one hour and twenty-four minutes) Wanda (Scarlet Witch) can disable the Vision, because she received her powers from the mind stone. One of Vision's powers is to manipulate his body density, so he can become phantasmal, or stronger than diamonds. She made him so dense, that he became too heavy to move, and fell through the floor.
Spider-Man's suit design is based on his original look in the comics when he debuted in 1962. The goggles change size to reflect Spider-Man's expressive eyes in the comics, and also allow him to hone his senses and focus.
In the Civil War comic book series, Tony Stark builds Spider-Man an "Iron Spider" suit. It's red and gold, and laden with armor and gadgets. In this film, Spider-Man receives a suit in his normal red and blue cloth attire, but it does have gadgets.
According to Lola VFX, the visual effects studio who have worked on all three Captain America movies, in order to create the "young Tony Stark" illusion: "Every feature of the face and body needed to be addressed in some fashion. One thing that happens to all of us is that the skin of the face gradually lowers in certain areas, and needs to be 'lifted' back to where it was at the age in question. But other changes are incredibly subtle, such as increase in the way light reflects off the sheen of the skin, a reduction in the appearance of tiny blood vessels under the surface of some parts of the face, or more blood flow in the cheeks giving them that familiar youthful 'glow'. The shot was nearly four thousand frames long, with Tony Stark turning from one side to the other multiple times, physically interacting with other actors, and the set itself, and moving closer to the camera for a very long, uninterrupted close-up."
(At around one hour and forty-five minutes) When F.R.I.D.A.Y. shows Tony Stark the photos of Zemo, he asks if she's run facial recognition, to which she replies "What do I look like?" He said, "I don't know. I've been picturing a redhead." Kerry Condon, who voiced F.R.I.D.A.Y., is a redhead.
Robert Downey Jr.'s personal trainer Eric Oram stated that the trick to pitting Captain America against Iron Man "is to show Iron Man using the minimum force necessary to win the fight, and not to look like he's trying to go wild and kill somebody."
Zemo is the first primary antagonist of the Marvel Cinematic Universe movies to not be an enhanced supervillain. However, the first one ever, in the Marvel Cinematic Universe, was Wilson Fisk, a.k.a. Kingpin, on Netflix's Daredevil (2015).
Costume Designer Judianna Makovsky said her favorite character to design, was Paul Bettany's Vision. She said she dressed him very stylishly, with elegant cashmere sweaters and cardigans, and gave him one of the "dandiest accessories", an ascot. She said that even though it might not be visible in the movie, he's wearing an ascot in most of his civilian scenes.
After the "Civil War" crossover event in Marvel comics was complete, another big crossover event was "Secret Invasion", which revealed that the shape-shifting alien villains, The Skrulls, had been replacing key people in government and the super powered community for decades, and that they are at least partially to blame for leading to the events of the civil war as a means to soften human society for a full-scale invasion. Since the Skrulls are villains of the Fantastic Four, it had been assumed that Disney and Marvel could not use them in future films, but it was later discovered with the announcement of Captain Marvel (2019), that Skrulls can be used by Marvel Studios, as long as they don't include specific ones owned by FOX. However, the idea of a "secret invasion" in the Marvel Cinematic Universe is already very close to what happened when H.Y.D.R.A. revealed they grew inside S.H.I.E.L.D.
(At around one hour and twenty-seven minutes) On The Late Late Show with James Corden (2015), Paul Rudd admitted that much of Ant-Man's star struck reactions to meeting Captain America and his allies, were greatly based on his own real first reactions upon meeting those cast members. He even owned up to the inappropriate "arm fondling" bit, though it was in fact Sebastian Stan's mechanical arm he was so interested in, rather than Captain America's, as depicted in the film.
Martin Freeman described Everett Ross as someone who "Works for the American government, and works in conjunction with the superheroes, and certain agencies that help to tame the superheroes' power." In terms of whether Ross would side with Stark or Rogers in the film, Freeman said that Ross is "ambiguous" and "You don't know whether he's good or bad", so "You're not quite sure which side he's on. It looks a little bit like he's playing one game, when actually he's playing another."
(At around two hours and ten minutes) During the Battle of the H.Y.D.R.A. Siberian Facility, when Captain America is asked by Iron Man to stand down, he responds, "I could do this all day." This is phrase is also said twice in Captain America: The First Avenger (2011), when Steve Rogers is beaten by a bully in an alley, and later by Red Skull. Rogers is rescued or helped directly after the sentence is stated.
Thaddeus E. "Thunderbolt" Ross' first appearance in the Marvel Cinematic Universe since his debut in The Incredible Hulk (2008). To date, that is the longest gap between a character's appearances in the Marvel Cinematic Universe (eight years). Despite the long absence, William Hurt reprised the role, though Ross is now Secretary of State, as opposed to a General in The Incredible Hulk (2008). This also makes William Hurt the first actor from The Incredible Hulk (2008) to return in a later Marvel Cinematic Universe film, aside from Robert Downey Jr. and Stan Lee, who had cameos in The Incredible Hulk (2008).
The words to activate The Winter Soldier were, "Longing, Rusted, Seventeen, Daybreak, Furnace, Nine, Benign, Homecoming, One, Freight Car". Most of these words had a meaning specific to him, and some have meaning in the MCU (such as "Homecoming" alluding to "Spider-man Homecoming").
(At around one hour and twenty-nine minutes) In the scene at the airport, when Iron Man calls upon Spider-Man to reveal himself and snag Captain America's shield, he does so shouting "Underoos!" Underoos are a line of children's underwear first released in 1977 that feature superheroes on them. One of the more popular set of Underoos features Spider-Man.
John Slattery (Howard Stark) is only two years older than Robert Downey Jr. (Tony Stark, Howard's son). But, since his final scene is set twenty-five years earlier (in 1991), that makes Howard twenty-seven years older than Tony.
In Spain, the film was titled "Capitán América: Civil War". The decision for not translating the subtitle "Civil War" as "Guerra Civil" was an attempt to avoid links or comparisons with the Spanish Civil War (plainly named in the country as "Guerra Civil"), which was fought between July 17, 1936 and April 1, 1939.
(At around one hour and thirty minutes) Tony Stark warns Captain America's side that if they don't surrender to Stark, some "J.S.O.C." guys will come after them instead. This is a reference to the U.S. Military's Joint Special Operations Command. J.S.O.C. oversees elite units like the U.S. Navy's S.E.A.L. Team Six, the U.S. Air Force's 24th Special Tactics Squadron, and the U.S. Army's Delta Force and 75th Ranger Regiment.
In the comics, while Spider-Man started off on Iron Man's side, he later shifted over to Captain America's side after learning that the Pro-Registration Side was imprisoning the captured unregistered heroes in a prison built in another dimension known as the "Negative Zone", against their will, without due process (as it is technically not on American soil) until they agreed to register. In this movie, he fights on Iron Man's side, before being sent home by Iron Man after the battle at the airport in Germany.
(At around one hour and seven minutes) While fighting Bucky Barnes, Black Widow tells him, "You could at least recognize me." This may be a reference to a storyline in the comics, involving the link between the Winter Soldier and the Black Widow programs that enhanced them both with biotech. It may also be a reference to their comic romantic involvement, or it refers to the Marvel Cinematic Universe story she told in Captain America: The Winter Soldier (2014), of being shot by him while on a mission, and various scenes in Captain America: The Winter Soldier (2014), when he was trying to kill her.
The working title that was used to create the film was "Sputnik". In the comics, "Sputnik" used to trigger the Winter Soldier's mind control, much like the sequence, "Longing, Rusted, Furnace, Daybreak, Seventeen, Benign, Nine, Homecoming, One, Freight Car", for his cinematic counterpart.
(At around fifty-seven minutes) In the film, when Bucky, Captain America, Falcon, and Black Panther are first captured, Bucky is placed in a cell marked "D23". "D23" is the official fan club for The Walt Disney Company and the fourth D23 Expo was held on August 14-16, 2015 at the Anaheim Convention Center in Anaheim, California, where the first footage from the film was screened.
Mutants (such as the X-Men) play a part in the original comic book story, as human society had always held a prejudice against mutant-kind, while also being accepting of non-mutant heroes. When the tide turns against all powered people, some characters view it as fitting, since non-mutant heroes had it easy for so long, and others view it as troubling. Since Twentieth Century Fox owns the rights to the Marvel concept of "mutants", this wasn't a part of the film.
(At around one hour and thirty-five minutes) Ant-Man (Paul Rudd) says the phrase "I'm your conscience, we haven't spoken for a while." The same phrase was used by Marlin in Finding Nemo (2003). These lines are references to Pinocchio (1940), to which Ultron also refers, in Avengers: Age of Ultron (2015), by quoting "I've Got No Strings".
(At around forty-three minutes) When Bucky Barnes (Winter Soldier) is in Bucharest, Romania, he is shown to be buying plums at a fruit market. Plums are beneficial in treating those with Alzheimer's disease, which therefore is suitable for Bucky, because he has been brainwashed, and is trying to remember his life before becoming the Winter Soldier.
(At around one hour and twenty minutes) During his meeting with Tony Stark (Robert Downey Jr.), Peter Parker (Tom Holland) tells him that he's only had his powers as Spider-Man for six months, clarifying the character's lack of involvement in previous Marvel Cinematic Universe films.
With a budget of two hundred fifty million dollars, this movie is tied as the fourth-most expensive superhero movie ever made, after Justice League (2017) (three hundred million dollars), Superman Returns (2006) (two hundred seventy million dollars), and Spider-Man 3 (2007) (two hundred fifty-eight million dollars).
According to the commentary, Cap dropping the shield foreshadows the appearance of the Nomad costume, a short period in the 1970s comics, where Cap continued to act as a hero without government sanction.
Spider-Man has two costumes in this movie, his original makeshift one he's seen wearing in YouTube footage, and which Tony Stark eventually finds in Peter's apartment, and his new costume, created with Tony's collaboration, which more closely resembles the classic costume.
Although Spider-Man's suit was composed of CGI for every scene, a physical prototype Spider-Man suit was built during production, that Tom Holland wore on-set during some filming. It wasn't until later, that the filmmakers decided to scrap the suit altogether, and replace it with a CGI version. The prototype suit differed from the final product on-screen, as it featured raised webbing, and a classic spider symbol, which was very reminiscent of the symbol shown in the very first Spider-Man comic, released in 1962.
This is the first movie in the Marvel Cinematic Universe where Tony Stark used only one Iron Man suit. In Iron Man (2008), Tony used the Mark I to escape the cave, the Mark II to experiment with the tech, and the Mark III to attack the Ten Rings, and his final battle with Stane. In Iron Man 2 (2010), Tony used the Mark IV at the beginning, the Mark V during his fight with Vanko at the Grand Prix, and the Mark VI in the final battle. In The Avengers (2012), Tony used the Mark VI for most of the movie, and then utilizes the Mark VII for the battle of New York City. In Iron Man Three (2013), Tony used the Mark XLII, the silver centurion armor, the Mark XL and the "Heartbreaker" armor in his battle with Killian. In Avengers: Age of Ultron (2015), Tony utilized the Mark XLIII in the opening scene, and in his initial battle with Ultron. Then Tony used the Mark XLIV (Hulkbuster) armor against The Incredible Hulk in South Africa. Finally, Tony uses the Mark XLV in the battle of Sokovia. In this movie, Tony only used the Mark XLVI.
Alfre Woodard plays Miriam, the mother of a young man who was killed during the events in Avengers: Age of Ultron (2015) in Sokovia. In the Civil War comic book, Miriam's son (named Damian, who was in grade school in the comics) was killed when a battle that reached his school between the super hero team New Warriors and some bad guys, (including Nitro, whose powers include him being able to explode and reconstitute himself afterward) destroyed a nearby school bus, causing a large gas explosion that destroyed the school, which caused hundreds of deaths, and was the impetus for the Superhero Registration Act.
This is the fourth film in the Marvel Cinematic Universe to feature a pre-Marvel Studios logo "cold open" scene. The first was Iron Man Three (2013), the second was Guardians of the Galaxy (2014), and the third was Ant-Man (2015).
(At around thirty-three minutes) Part of Sharon Carter's eulogy for Peggy Carter was written as part of the Marvel Civil War in the Spider-Man comics by J. Michael Straczynski, Writer and Creator of Babylon 5 (1994), and credited for the story for Thor (2011). The speech comes from an inspirational speech Captain America gave to Spider-Man during the Marvel Civil War, to explain why he continues to fight against the Superhuman Registration Act, when the country he represents is all for it. As a child, Captain America memorized a monologue that influenced his understanding of what it meant not only to be a patriot, but what it really meant to be an American. The whole philosophy stems from the writing of Mark Twain, in a monologue known as, "In a Republic, who is the Country?"
(At around thirteen minutes) During the virtual reality scene at M.I.T., Maria Stark (Hope Davis) plays the piano and sings the song "Try To Remember", from the 1960 musical The Fantasticks. This song's lyrics link nostalgia for the month of September, with the singer's lost youth: "Try to remember the kind of September / When life was slow and oh, so mellow / Try to remember the kind of September / When grass was green and grain was yellow / Try to remember the kind of September / When you were a young and callow fellow..." After Maria finishes singing, and the virtual reality presentation is done, Tony (Robert Downey Jr.) announces to the M.I.T. students, that he has given them grants for all of their research projects under the auspices of his new foundation, the "September Foundation".
This was the first theatrically released film, featuring Spider-Man, where the visual effects for the character are not being produced by another company affiliated with Sony, the rights holder to Spider-Man. Industrial Light & Magic, which handles much of the special effects for the Marvel Cinematic Universe, produced the visual effects.
Earlier drafts of a third Captain America film, had Brock Rumlow, a.k.a. Crossbones, secretly working as a mercenary for the Red Skull (just like in the comics), but these ideas were scrapped and re-worked, when the filmmakers decided to follow the "Civil War" storyline.
Multiple references to different themes that aren't related to the Marvel Cinematic Universe are made throughout this movie: While confined, Falcon tells Iron Man to bring Mark Fuhrman if he wants him to talk (Mark Fuhrman was a key part in the 1994 to 1995 O.J. Simpson trial, having been thought to frame the football player because of his hatred towards black people), and during the final scene in Siberia, Iron Man calls Bucky Barnes "Manchurian Candidate", referring to the twice-filmed novel, in which American soldiers were brainwashed.
Bucky's code name "Winter Soldier" could have multiple sources of meaning. Winter could represent his maintenance, as he is kept on ice whenever he's inactive. It could represent that he is a relic from The Cold War, or that his humanity was stripped, to make him the coldest of assassins.
(At around one hour and forty minutes) When Redwing hits Iron Man in the head during the airport scene, a circle of "feathers", possibly shrapnel, can be seen, as a reference to when characters are hit in cartoons or comics.
The Raft, in the comics, is a facility in New York City, which is part of Ryker's Island Penitentiary, that is designed to hold captured supervillains, which is run by S.H.I.E.L.D. In the film, it is located somewhere in the Atlantic Ocean, and run by the U.S. Military instead, as S.H.I.E.L.D. has been disbanded. Notably, the first storyline of the New Avengers series, which started not long before the Civil War crossover event began, involving the prison riot, was actually the Raft's first appearance in the comics. While the Raft was not used in the original Civil War comic book storyline to hold the captured superheroes, it was mentioned though.
Every phase of the Marvel Cinematic Universe starts with a film that features Tony Stark as at least one of the main characters. Phase One started with Iron Man (2008), Phase Two started with Iron Man Three (2013), and Phase Three started with this movie.
The first movie to be shot with the Alexa IMAX camera, featuring fifteen minutes of footage. The Alexa IMAX camera was a collaborative development between Arri and IMAX, in customizing the Alexa 65 6.5k camera to facilitate viewings in IMAX theaters, without overhauling equipment.
Although she is never mentioned as a mutant (Twentieth Century Fox owned the term rights at that time), Scarlet Witch is the only mutant among The Avengers in this movie, and she is seen with a collar when locked in Raft Prision, which can be a reference to the X-Gene Inhibitor Collar, created in the comics by Bolivar Trask to suppress mutant powers. The collar has been featured before in X-2: X-Men United (2003) and X-Men: Days Of Future Past (2014).
(At around one hour and sixteen minutes) When the film introduces Peter Parker in Queens, the introduction shot is behind him, showing the character casually holding a DVD player against the side of his body. In The Amazing Spider-Man (2012), one of first few introductory shots of Peter Parker (Andrew Garfield), had the character holding a skateboard in a similar manner, with an almost identical frame composition.
When Tony presents the pens from his father's archives, he says that it "felt timely". The company Marvel Comics was originally called Timely Comics. Theoretically this could be an obscure Easter Egg, but is probably just a coincidence.
Stan Lee's second cameo playing a delivery man. In this movie, he played a FedEx driver delivering a package to Tony Stark (Robert Downey Jr.). In Fantastic Four (2005), he played Willie Lumpkin, a USPS mailman who delivered Reed Richards' (Ioan Gruffudd) mail to him early in the movie.
One of two films released in the same year which show the parents of a multi-billionaire superhero being murdered. In this movie, Tony Stark's parents are murdered in a flashback. Batman v Superman: Dawn of Justice (2016) had a scene where the parents of Bruce Wayne are murdered. Bruce Wayne and Tony Stark share a lot of common characteristics. Both are extremely intelligent superheroes with no superhuman powers other that their gadgets and suits. Tony Stark is the CEO of Stark Industries (founded by his father), whereas Bruce Wayne is the CEO of Wayne Corp (founded by his merchant ancestors).
Hope Davis (Maria Stark), is only one year older than Robert Downey Jr. (Tony, Maria's son). But, since her final scene is set twenty-five years earlier (in 1991), that makes Maria twenty-six years older than Tony. Davis and Downey co-starred in Charlie Bartlett (2007).
Captain America: Sentinel of Liberty, was a planned 1981 Universal Pictures movie, which would have featured Jeff Bridges as Captain America, Peter Fonda as Red Skull, Alan Rickman as Baron Zemo, Clarence Gilyard Jr. as The Falcon, Erin Gray as Sharon Carter, and Martin Sheen as Senator Lance. It would have been directed by Kenneth Johnson. It was written by Jeffrey Sprouse with a thirty-five million dollar budget. The movie never materialized, due to the fact that Universal Pictures could not re-acquire the rights.
Alfre Woodard, who makes a cameo in the film as Miriam, the woman who blames The Avengers for her son's death, when The Avengers fought Ultron in the battle of Sokovia. Alfre had appeared in another science fiction film about cyborgs, Star Trek: First Contact (1996), as Lily Sloane.
Paul Rudd (Scott Lang (Ant-Man)) uses his Pym Particle-powered suit to turn into Giant-Man for the first time on-screen. In Monsters vs. Aliens (2009), Rudd played the fiancé of the main character Ginormica (Susan Murphy), who also becomes a gigantic humanoid monster with amazing strength, after absorbing the radiation from a comet made of a rare element.
Tom Holland (Peter Parker/Spider-Man) has worked with brother and sister, Tom Hiddleston (Loki) and Emma Hiddleston in separate projects. Tom worked with Tom Hiddleston in the Marvel Cinematic Universe (they both appeared in Avengers: Infinity War (2018)) and Emma Hiddleston in Wolf Hall (2015), where they played Gregory Cromwell and Meg More respectively.
Alfre Woodard: (At around seventeen minutes) as Miriam Sharpe, the mother of an American citizen killed in the battle of Sokovia. Woodard was suggested for the role by Robert Downey Jr. before Marvel Studios learned of her casting as Mariah Dillard in Luke Cage (2016).
The trivia items below may give away important plot points.
The filmmakers describe betrayal as a crucial theme in the film: "We didn't want the movie to be just about politics, and people arguing about platitudes. The final act is built around a personal act between Tony and Steve."
(At around two hours and ten minutes) In the climax, before destroying the suit's arc reactor, Cap tears the Iron Man helmet from Tony's face. If he had not done this before the suit lost power, Stark likely would have suffocated, implying that Rogers was simply trying to end the fight, rather than kill Tony.
In the movie, Rhodes' (Don Cheadle) spinal column is severely damaged as the result of an accident while he was in the War Machine suit. As a result, Rhodes uses bionic supports on his legs to move around during his recovery. This is a nod to an incident in the comics when Rhodes was badly injured, and had to receive cybernetic implants for his legs, arms, and part of his face making him part cyborg (similar to DC Comic's Cyborg, who is also a black superhero with cybernetic implants) which lasted until Marvel's Dark Reign event, where Rhodes received a new cloned body, into which his mind was transferred.
In the comics, the second Giant-Man, Bill Foster, is one of the Anti-Registration heroes, who was killed by Thor's clone Ragnarök during the first battle between both sides. The concept of Scott Lang becoming Giant-Man to fight back against Iron Man's team (who was incapable of enlarging himself in the comics) as well as War Machine being injured as a result of Vision's attack (though it was accidental) are similar to this.
In Captain America: The Winter Soldier (2014), Captain America, Black Widow, and Falcon were arrested by H.Y.D.R.A. posing as S.H.I.E.L.D., which they escaped, having been freed by Maria Hill. In this movie, Captain America, Falcon, and Bucky were arrested by German Special Forces, and escape after Bucky (as the Winter Soldier) goes rogue, with help from Agent 13 Sharon Carter.
This is the second film, featuring Don Cheadle, in which a "pinch" is used to set an electromagnetic pulse that interrupts the electrical grid. In Ocean's Eleven (2001), rogue explosives expert Basher Tarr (Cheadle), uses one stolen from a research lab to shut down Las Vegas' electrical grid while his partners in crime robbed three casinos. In this movie, the villain Zemo ships a pinch to unwitting workers at a substation. The workers unwittingly trigger the pinch, and Zemo, posing as a psychologist sent to examine Bucky after he was captured in Germany, uses the ensuing blackout to interact with Barnes unobserved, and trigger Barnes' Soviet "Winter Soldier" programming. Nothing good comes of it.
This movie is considered to be the Star Wars: Episode III - Revenge of the Sith (2005) of the Captain America trilogy (2011, 2014, 2016). A vengeful Zemo causes a rift between Captain America and Iron Man and tears The Avengers apart, and exposes the truth behind the death of Tony Stark's parents to manipulate and force Captain America and Iron Man to turn on each other and fight.
An "avenger" is a person who seeks revenge upon those who have wronged themselves or others. Iron Man and Black Panther both seek revenge upon Bucky Barnes. Bucky is framed for the murder of Black Panther's father, and, while brainwashed as the Winter Soldier, assassinated Tony Stark's parents at the order of H.Y.D.R.A.