Ever since the manga revealed that the world is sinking/flooding, I’ve believed like a lot of other fans that the Ancient Kingdom was basically Oda’s version of Atlantis: a highly-advanced utopia that now sits at the bottom of the ocean because of its hubris. I’m not saying it’s the “name” of the Ancient Kingdom but we’ll get to that.
Anyway, I’ve been trying to reason out why Joy Boy would’ve had Ancient Weapons capable of so much destruction in the first place. And why 20 kingdoms agreed to risk it all and rise up against this one powerful kingdom. It very much suggests to me that Joy Boy was affiliated with an oppressive nation doing some pretty terrible things while he was off having an adventure that would shape and change him.
I’ve come to the conclusion that he might’ve been a fishman, and the Ancient Kingdom was a Fishman Kingdom. In fact, I like the idea that Joy Boy was their prince or something before becoming the first pirate.
We know the world before and during the Void Century was quite different from the one today, and it likely had a lot of wars between different races like Giants, Buccaneers, Minks, Lunarians, and yes, Fishmen all vying for control.
But Fishmen have always had the unique advantage of being able to live on both land and sea. They probably didn’t rule the whole world, but may have been the most advanced civilization and were crusaders like Rome/Greece in that they were conquering different lands and kingdoms and subjugating people into their empire. Against humans, for example, they were the obvious superior species save for, you guessed it, the devil fruits.
Which brings me to what their aim truly was. The Ancient Weapons could’ve been their grand plan to flood the entire world, so they’d truly dominate everything. It would severely limit the capabilities of Devil Fruit users and In their minds, it would be the solution to endless war and strife…by their own great cleansing. Sort of like how Ozai in Avatar: The Last Airbender decided to just wipe out the Earth Kingdom to truly end the war for good.
But before the Ancient Kingdom truly carried out this plan, Joy Boy “set out to sea” by leaving the Pangea continent (or sailing to it?) and broke away from his royal responsibilities to see the world and get to know other races.
Joy Boy made lots of friends along the way — Zunesha, the Iron Giant, maybe even Toki — and slowly began to change as a person. Maybe even be inspired by the Sun God Nika to liberate the world and take its form eventually. This would culminate with him meeting Imu and Lili, and him promising to help them stop his own people — including whoever Poseidon was at that time — from using the Ancient Weapons and ushering in an era of peace.
But somewhere along the way, Joy Boy was either betrayed by his crew or he betrayed them. Maybe he found out that Imu planned to use the Ancient Weapons to still flood the world but by destroying the Ancient Kingdom and doing a genocide against all Fishmen, even the innocent ones. And then reshape the world to have the edges of the big Pangea continent to serve as a red line separating all people and seas, which would go fully against the point of uniting the world.
As you can imagine, this was probably Imu’s plan, with Lili siding with him because as humans(?) their trauma as second class citizens would inspire them to prevent that harm from happening to their people again. Hence, Imu’s fascination with Vivi could be him seeing history repeat itself with the new Joy Boy finding a Nefertari who will go against him like Lili ultimately did because she saw him falling to corruption and becoming the evil he once fought against.
The initial idea of a “world government” was an idealistic one, down to having a throne with no one on it, but in his paranoia, Imu betrayed those ideals like he did Joy Boy.
Joy Boy was “defeated,” but not because it was a matter of losing a fight necessarily. He wasn’t able to stop Imu from using one or two of the Ancient Weapons. The plan to sink the world succeeded, so Joy Boy had to prepare a plan to fix this in the future, knowing it could take centuries. He had to die so his devil fruit could safely be used in the future to reverse this or prevent something even worse from happening.
Maybe Poseidon (their last Ancient Weapon) created the calm belt and commanded the Sea Kings to effectively divide the sea in the meantime, so that at least some of the world could be free from the world government (until Vegapunk came along and created battleships that could traverse the calm belt). And so by the end of the story, Poseidon can use the Sea Kings to eradicate the calm belt and create the new All Blue.
I could also see Joy Boy instructing his friend Toki to go forward in time with his devil fruit after he dies (maybe with Lili’s help) so it’ll be protected from Imu until the time is right. Speaking of, this would explain why the World Government despises Fishmen and drills it into the Celestial Dragons that they’re “gods” compared to all other races. That stems ultimately from Imu’s twisted ideology after being oppressed at the hands of Fishmen.
Other clues for this include the symmetry of Jimbei’s “Sun Pirates” and Joy Boy being the manifestation of the “Sun God,” so connecting Luffy to the liberation of the fishmen people reaching the Dawn. The first we EVER hear about Joy Boy is during the Fishman Island arc. Luffy’s first serious opponent is Arlong. In the recent silhouette we see of Joy Boy in Gear 5th, he doesn’t look like a giant or buccaneer like many have speculated.
I also suspect that the devil fruit weakness to water speaks to how the world shifted in power when fishmen ruled everything, and sinking the world would seriously tip things in their favor. Lili scattering the Poneglyphs also feels of a kind with Joy Boy’s ultimate plan for someone to end the war someday by reaching Laugh Tale.
Finally, I think the world government would have every reason to fear the name of the ancient kingdom coming out if it was something like “Fishman Empire” since that would reveal to the world that fishmen used to be on top.
And narratively, I really like the idea of Joy Boy’s downfall coming down to a complicated relationship between him and his own people (like Poseidon), where it’s morally gray instead of a basic good vs. evil thing. It rings of both Alabasta and Wano, with Joy Boy being a mix of Oden and Roger. He wants to see the world but is unaware of how freedom will change him for the better. I think this is where the concept of the One Piece and what truly is might come into play.
Obviously there’s way more to connect here like the Noah for obvious reasons and the voice of all things, Poseidon coming back as Shirahoshi, the true nature of the Gorosei, that big straw hat, the D clan, and so on. But at the risk of turning this into a novel, I’ll stop here for now!
Theory by rookiepirateradio (https://www.reddit.com/user/rookiepirateradio)
