(Before I begin, I want to let everyone know this is a theory. I am well aware that the film rights to Namor belong with Universal.)
Namor the Sub-Mariner is Marvel's Aquaman. The two are pretty much the same. Now Namor has had much history with the Marvel Universe, including with Invisible Woman, The X-Men, and Captain America.
Now, let's dial the knob back to 2011 when Captain America: The First Avenger was released to the public. Remember that one scene that foreshadowed the second Captain America Movie?
I want you to notice something here. Bucky falls towards a river of some sort in this shot, but in Cap 2, Arnim Zola is ordering his men to lift him from the ice. You may argue that Bucky doesn't land in the river, but I think that if he really fell from that high up with that much speed, his impact should've cracked the ice. Anyways, we know that Zola couldn't get him for quite a bit of time because he was captured immediately after this scene. Than he was held prisoner for a while until S.H.I.E.L.D. was formed. Obviously, he had to wait until S.H.I.E.L.D. gained his trust to go out and do any research or search for Barnes.
So my question is, when Zola found Barnes, why was he still alive? Just bear with me, some of you are probably confused.
As long as Zola was prisoner, Bucky had stayed put right? So after all that time, Bucky managed to survive somehow? I think that this was the work of the Atlanteans and Namor. Maybe this was in a time where The Atlanteans weren't hateful for humans, and they decided to get this one out of the water as soon as he landed. Wait, Bucky lost his hand though....
This probably proves Bucky hit the ice and not the river, but maybe he survived the impact because of Atlantean magic. He might've been healed by them, but he had lost so much blood that he was unconscious for periods of time while the Atlanteans fed him and cared for him, kind of. Now the question is, how did Zola know where Bucky was?
The Easter Egg
This S.H.I.E.L.D. map shows several parts of the world highlighted. While you could say none of these are super humans, why in the world is there a bullet in the middle of the ocean?!? Everyone is believing this to be Namor, and I think it is too. But what if S.H.I.E.L.D. had this map long before Ironman 2? What if it dates back to Cap 1?
Maybe Zola and S.H.I.E.L.D. developed the program to be able to find unusual activities around the world? If this is the case, Zola might have seen the point in the middle of the ocean and been more curious than the rest of S.H.I.E.L.D., causing him to go look for the source of the bullet. Zola finds the city of Atlantis (or whatever it's called in Marvel) and begins interacting with the citizens and trying to get them to change their beliefs on humans. Zola's talks attract one mind in particular...
The young future villain would befriend Zola immediately and share in the same beliefs, eventually telling him about a human they are caring for on the shores. Zola proceeds to gather his HYDRA squad and is astonished to find Bucky Barnes in a terrible state, but alive. Then comes the Winter Soldier.
Captain America Too Had an Encounter
Even with the Super Soldier serum, how could a man survive 70 years in ice and be completely normal after some lamps are turned on around him? Atlanteans've got magic, right? Maybe he wasn't frozen in normal ice, but the Atlanteans created a magical ice encasement around him that froze his body, but kept his mind living and well.
But how does this relate to Namor?
Several reasons could cause a distrust between humans and Atlanteans:
If S.H.I.E.L.D. knows that underwater beings are out there, they're probably keeping in touch. Therefore, Namor might have ascended to the throne and is skeptical of all the above water activities taking place. Ironman himself might be a good enough reason to start hating humans. All the pollution from his weapons, the radiation, even the Stark Tower light-up switch in the river might be killing off natural sea life. This might cause a decrease in Atlantean food sources. Next, if Attuma really did talk with Zola all those years ago, they probably kept up with conversation. HYDRA gained a new ally underwater, and Attuma gained allies above to help remove Namor from the throne or cause a war between the two species.
Well, what do you think? Good theory? Bad theory? Be sure to let me know in the comment box below.