The original Millennium earl split into two babies, Nea and Mana. Both of these children grew up as twins but Mana slowly went mad because there was a voice in his head telling him to kill Nea and become the new Earl.
When a Noah dies, their memories get damaged and Nea knows something big we don't know what yet so he tries to protect his memories before Mana eventually kills him.
He finds a random soldier named Allen (first version) they make a deal. Nea fulfills Allen's wish and in turn, Nea can store his memories in Allen's head so when he revives in 30 years he can wake up in Allen's body with his memories intact.
Mana manages to kill Nea but goes insane with grief and kills himself.
Apocryphos is an immortal being who's tasked with protecting the heart of the innocence and he knows Allen made a deal with Nea so he goes after him.
Lavi was a bookman tasked with recording the war but he was so fascinated with Nea he abandoned his duty to to run after him, he later meets Allen on the way and they start traveling together.
Apo tries to let Helix of Life consume Allen for the greater good and Allen's body unravels / de-ages, turning into a child and losing a great deal of his memories.
In the helix, Allen gets chosen by the innocence because innocence is always drawn to people with tragic fates.
Lavi then jumps into the Helix and pushes Allen out so he can get consumed instead. I think a little bit of his soul got mixed in with Allen's? I'm not that clear on that part either.
Apo spares the now freshly traumatized amnesiac Allen (the second version we know as the MC) because he can grow up to be an exorcist.
In the circus arc, Mana revives as an old man who doesn't remember his past and instead works in a circus. He doesn't remember Nea or what happened to him but he knows he's missing someone. That's why he joined the circus, so he can travel all over the world to look for him.
Allen was a ''weirdo orphan'' nobody wanted so he joined the circus too as a cleaner / server.
Mana doesn't remember his past but he remembered the name ''Allen'' so he named his dog after him.
Another member of the circus was jealous of Mana's success so he ends up killing his dog and Allen cries with Mana after learning about it. After this they get very close but once MC learns about the real reason for Allen's (dog) death, he gets enraged and activates his innocence to kill him.
!!!I'M NOT 100% ABOUT THIS PART EITHER!!!
Mana tries to stop him but Allen accidentally hurts him with the innocence. After tasting innocence, Mana's inner Noah rage awakens and ends up killing everyone in the circus.
I don't remember what happened after that but basically Mana goes insane and forgets himself. He thinks MC is his dog Allen so they travel alone. Mana still carves symbols on trees (he doesn't remember Nea and what the symbol means but he still leaves it on places so the person he was looking for can find them and follow him)
One day Mana peacefully passes away in his sleep and after that I'm not 100% again but I think after Mana died he fully awakened as the Millennium Earl and tried to take advantage of Allen's grief to revive the original body of Mana and get rid of Allen.
Then he gets cursed yada yada you know the rest.
Forgot to add but from what I know, the world Noah lived in got ''purified'' which basically made it inhabitable for them so they're trying to take over this one to make it their new home
Some things I forgot: Allen basically died when Nea awakened but Johnny called out his name and the idea is that the voice of a loved one can pull your soul from the other side so Allen basically got soul bonded to his own body. He's pretty much an akuma right now.
Lavi got kidnapped by Desires because he likes playing house with his Noah brethren and he sees Road as his daughter (it's not clear if they're actually related)
so wants to know if anything happened between Road and Nea before he became Allen.
Allen and the gang went to the bookman household to learn what actually happened to Allen (Basically the recorder bookman goes and witnesses the war and the rest automatically learn it because they share the knowledge like bluetooth because they have the same blood)
The bookman clan hates Allen because Lavi 1.0 abandoned his post for him and they want to know what happened to him. Allen accepted a truth pill (?) that can show him his past.
Thank you so much for this! I just copy pasted this whole thing into the comment/summary of the series so i can reread it again when i forget again this whole madness, you are awesome
happy to lore dump about my fave manga of all time
I feel dumb for not grasping what's going on... like I feel like I understand it then I don't.... I need some one to explain to me the current lore of dgm