Among fans, the relationship between Steve Rogers and Bucky Barnes might be the most popular in the MCU. While Steve found his happy ending with Peggy Carter and Bucky began a new partnership with Sam Wilson, there is no denying the connection these two lifelong friends shared together.

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Having been through so much together, from their younger days to their time in the war to making sense of the 21st century, there are countless quotes that cement just how important this friendship was. And these memorable lines make it clear why fans love Steve and Bucky together.

Steve's New Look

Bucky: "You're Keeping The Outfit Right?"

Bucky smiles at Steve at the bar

While Steve Rogers was undoubtedly the right man to become Captain America, having a friend like Bucky likely helped to keep him grounded. It takes a very good friend to still give someone a hard time even when no one else will.

Obviously, when Steve shows up with his flashy Captain America uniform, Bucky can't just ignore it. Even after Steve saves an entire platoon, Bucky still is sure to poke some fun at his old friend's new look, if only to remind him how ridiculous it all is.

Sticking Up For Steve

Bucky: "Pick On Someone Your Own Size."

Bucky and Steve in Captain America The First Avenger attacking

While Steve would end up saving Bucky plenty of times once he became a super soldier, their roles are very much reversed when Steve is still just a skinny kid from Brooklyn. While Steve is getting beat up by a bully in an alley, Bucky shows up to put the bully in his place.

Steve is not someone who would ever ask for someone to fight his battles for him and he would never back away from a bully. But with a mentality like that, Steve is lucky to have a friend like Bucky who is there to look out for him.

Childhood Memories

Bucky: "This Isn't Payback, Is It?"

Steve and Bucky on top of a train in Captain America: The First Avenger

Given the wild universe-saving adventures they go on, it's easy to forget that there was a time when Steve and Bucky were not Captain America and the Winter Soldier. However, whatever they are facing, these two friends seem to always those simpler times.

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During the war, Steve and Bucky prepare for a dangerous mission, boarding a Hydra train. Before they set out, Bucky reminds Steve of the time he forced Steve to ride a rollercoaster until he vomited and wonders if this is Steve's revenge. Even in the midst of danger, they can share a joke like childhood friends.

Saying Goodbye

Steve: "How Can I? You're Taking All The Stupid With You."

Bucky hugs Steve in Avengers Endgame

Even though both of these heroes have chemistry and interesting relationships with other characters, there is a rapport between them that is undeniable. Their long history going back to Phase 1 can make for touching callback moments throughout the franchise.

When Bucky heads off to war, he teases Steve not to do anything stupid while he's gone to which Steve responds, "How can I? You're taking all the stupid with you." This moment is repeated in Avengers: Endgame when Steve heads back in time and has become the special "goodbye" between these friends.

Proving Himself To Steve

Bucky: "Your Mom's Name Was Sarah. You Used To Wear Newspapers In Your Shoes."

Steve returns with Bucky and the 107th in Captain America The First Avenger

Despite their incredibly strong relationship together, it is all almost torn apart when Bucky emerges as the Winter Soldier. All that history and love he shared with Steve is erased and Steve no longer knows if he can trust him.

However, in the friend he was years ago. With that connection, Bucky is able to regain a bit of his humanity.

A Long History

Bucky: "She's Gotta Be A Hundred Years Old Right Now." Steve: "So Are We, Pal."

Chris Evans as Captain America Steve Rogers and Sebastian Stan as Bucky Barnes Winter Soldier in Civil War

Another moment in which Steve and Bucky take a moment in the midst of their big heroic mission to look back at their young days comes in Captain America: Civil War. They reminisce about two girls they knew back in the day.

Bucky speculates that they must be 100 years old at this point to which Steve reminds him that they are as well. It is a moment that cements the oddly touching way that these two friends understand each other more than anyone as they find themselves out of time.

Choosing Sides

Steve: "He's My Friend."

Steve carries Bucky while they're both injured

The rivalry between Steve Rogers and Tony Stark has always been a fun part of the MCU, but that relationship took a dark turn in Captain America: Civil War. Unfortunately, at the center of that friendship coming apart was the friendship between Steve and Bucky.

Once Tony learns Bucky killed his parents, he is deadset on revenge and Steve is the one standing in his way. Steve telling Tony that Bucky is his friend makes it clear that there is no other possible choice and he has chosen Bucky over all else.

Bucky's Doubts

Bucky: "I Don’t Know If I'm Worth All This, Steve."

Bucky and Steve Team-Up in Captain America: Civil War

Though there are a number of tragic figures in the MCU, bucky might have them all beat. Aside from living decades as a brainwashed weapon, Bucky is then forced to live with the memories of everything he has done.

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Along with that pain, Bucky sees the consequences of saving him might have. In a vulnerable moment, he its to Steve that he might not be worth it. It is a selfless moment of Bucky looking to save his friend and Steve immediately dismissing that idea.

Following Steve Into Battle

Bucky: "That Little Guy From Brooklyn Who Was Too Dumb Not To Run Away From A Fight. I'm Following Him."

Steve and Bucky in a flashback in The Winter Soldier

It is easy to forget that Steve Rogers was just a skinny kid from Brooklyn at one point. But while Captain America inspires countless people and even leads Earth's mightiest heroes into battle, Bucky still sees the kid he grew up with as the true hero.

It is not that Bucky is against Steve taking up the new mantle, but rather that he reminds Steve that he always had that heroic part inside him and he just now has the muscles to go along with it.

Never Giving Up On Each Other

Steve: "'Cause I'm With You 'Til The End Of The Line, Pal."

Steve with his hand on Bucky's shoulder in Captain America Civil War

Another line that became repeated by Steve and Bucky speaks to the heart of their relationship. it first comes about as Steve re when he lost his mother and bucky reminded him that he would always be there for him.

In Captain America: The Winter Soldier, this sentiment is used to remind Bucky who he is. Just as Bucky is about to kill Steve, Steve uses the line, showing that even in this moment, he is not willing to abandon his friend. It speaks to everything that these friends go through and how they stand by each other no matter what.

NEXT: 10 Best Steve Rogers/Bucky Barnes (Stucky) Ship Memes