Any MCU fan would have watched Avengers Endgame and saw how Captain America went back in time and stay in the past. Only for us to see old man cap passing the shield. Writers explain “Branch Timeline” however he travelled back to this timeline to pass the shield. Thus having not to explain what happened to Captain America staying hidden for over 70 years. but I have a new theory on this, despite what the writers say, what if Captain America was in the MCU past and lived through the history watching events unfold. “But what about the butterfly effect” well there has been more marvel properties since the original idea that could explain what Cap did.
For one, Loki series introduces the TVA. And they explained that the time travel that the avengers did was part of the sacred timeline and needed to happen. Ok but what about Caps divergence creating a branch. Well there is two trains of thought
1. There is only one timeline in the tva. The sacred timeline so in theory, cap could t of gone to a parallel world because it would go against Kangs plan with the one timeline.
2. Which would mean that Cap staying in the past, had to happen in that timeline. Not an alternative. But then what about the butterfly effect. Surely his return to the past with future knowledge would change the future?
My answer to this, yes, yes it would…unless he had help. See the TVA doesn’t always prune it’s variants some mindwiped becomes employees and in the case of Loki with no mind wipe did what he was supposed to do because it was always Kangs plan.
But as the TVA keeps the timeline in check, they would need to look for any variation branch timelines. This is where Cap becomes very useful. See he knows what is to come in that timeline, he knows how it should go. And he’s patriotic, he would fight to keep everything the same so no butterfly effect would occur.
So my theory is this, Captain America when he went back was picked up by the TVA, and given the usual explanation of variant branch timelines. But as he’s from that future he has a unique idea of what’s to come. And as he missed 70 years of live events he is less likely to trigger a butterfly effect because he was not there to witness how events went but only read about them. If he read about them at all. He wasn’t in the future for very long we don’t know how much of the past he researched. But we could denote he would have read at least some things.
TVA hired Captain America to become a TVA agent to help the 70’s of history unfold without variant branch ones by keeping it on track. I mean think of the scenarios he could have been involved with. Cap could have been responsible for Nick Fury becoming the director of shield. Considering he works with Peggy Carter in founding shield. Making sure they get the one person they can trust to lead shield in the future and nobody else takes that spot.
You could also cement this as a possibility because in one scene from Loki season 1 we saw a Peggy Carter be brought to the TVA. Maybe she wasn’t a variant but the actual Peggy Carter. See she’s linked with Cap so if cap has a new mission to keep the timeline on track he would need a trusted ally. That’s where Peggy comes in. The TVA brings her in explains Captains situation and how the both of them become honour members of the TVA.
This then brings me to my other theory, on Captain America being the grand parent of Captain Britain. Obviously Cap is missing in history, so he needs a new identity. A new masked hero called Braddock. Only Peggy knows who he is and as part of the guise he is a British operative liaison for shield. (Which coincides with what Peggy said in the 70’s) this switch of identity and possibly locating to England might be the cover. Then Peggy and Cap (now braddock) has a kid then years later become grandparents to a kid who would become the future Captain Britain if they ever introduce this character..
Timeline kept on track, history doesn’t diverge, TVA Happy.
planetnerdy 