In this post I'll try to gather all the informatuion we have of Meloetta and King Harmonia and create a narration that makes sense. I'll use the lore the games give to us, but also certainn episodes of the anime. I know anime is not canon in the games, but I'll expllain later why I think it could make sense in this particular subject.
Background
For those that don't know, here is the story of King Harmonia according of the information we know from the games (mainly the Abyssal Ruins and some books in Team Flare's headquarters):
Harmonia is the antecesor of N and Getchis. As N, Harmonia had the power of communicating with Pokemon and see the future.
Harmonia and AZ were brothers. They found the meteorite that contained the Original Dragon. Every one of them befriended one of the dragons, Zekrom (who sided with Harmonia) and Reshiram (with AZ). With the help of those Legendary Pokemon, they became powerful kings. AZ created (or at least ruled) the kingdom that would become Kalos. Harmonia ruled over the lands that one day would be known as Unova.
Harmonia started as a tyrant, hungry of power. He launched a war of inavsion over the kingdom of his brother. The forces of Harmonia were more numerous and were winning. Then, AZ's Floette persihed. Blinded by the desire of bring back his loved Pokemon, AZ created the Definitive Weapon, which effectiely resurrected Floette and destroyed Harmonia's army and castle, ending the war.
Seeing the destruction that war brings, Harmonia changes his mentality completely. He becomes an egalitarian king that seeks peace. Eventually, Harmonia passes away and some years later the kingdom ends. It's not clear the reason, although is implied that it could be because a tsunami. Nowadays in Unove, very few remembers King Harmonia and the culture of his kingdom.
King Harmonia is buried in the palace where he was crowned, which later would become the Abyssal Ruins.
Meloetta
What we know about Meloetta's past besaides the info the Pokedex gives us? Very little. We only have the event in Café Sonata. After showing Meloetta to the musician there, he teaches Meloetta Relic Song and says:
The scent you brought me reminded me of a long-ago melody from the firnges of my sepia-toned memories.
It was a song my mother loved…makes me feel nostalgic.
My mothe ronce told me of a Poekmon that played a melody and danced so lightly that it filled people's hearts with joy.
Then sorrow darkened the entire world, and the Pokemon lost the melody…
Also, at the time, some red shoes were lost somewhere…
When you came through the door, I remembered the melody!
And the pokemon that had forgotten how to dance began to step lightly once more!
So, Meloetta once knew the Relic Song, but something happened that made her sad (and the entire world) and forgot the song. Also, and I'm going to start adding my own thoughts here, as other Mythical Pokemon, Meloetta remainds hidden until she finds a "special" trainer (in the games, the MC). We see this with Mew and Shaymin, for example, so I don't think is a reach apply this behaviour to Meloetta (Do you rememebr all the things you have to do to find her in S/V?)
The anime
I know, I know. But I think the anime of the Black and White Season follows pretty closely the lore of the games, and what happened in Meloetta's episodes It fits pretty well with what we know, so I think is soemthing Game Freak thought of, or at least would approve for the lore of the games.
In the two episode BW096 Meloetta and the Undersea temple! Giovanni kidnaps Meloetta because she is connected to the Abysal Ruins, and can find the Reveal Glass there. In the next episode we find a group called The Protectors, the descendants of the people who lived in the castle that later was the Abyssal Ruins (remember, that was King Harmonia's castle), and their duty was to protect Meloetta so her power doesn't end in bad hands.
So what we have here is that the descendants of King Harmonia's Court had the mission of protect Meloetta, and she was very important to the kingdom.
The timeline
Now, I'm going to make my interpretation that what were the events that happened:
Meloetta was searching for a "special" trainer. King Harmonia was a better leader after the war, wanting peace and a better life for all his people. Also, he could communicate with Pokemon, and his name indicates that he has interest in music maybe?. I think he fits the bill of a "special" person.
Meloetta becomes King Harmonia's Pokemon partner. She's happy singing and dancing on the castle for all the court. King Harmonia eventually passes away. The castle is destroyed by a tsunami, or Meloetta sinks it like in the anime, whatever.
There are few survivors of King Harmonia's court and the rest of the world forgot the song.
Until she finds another "special" trainer (the MC), and the trainer remind her the Relic Song.
Anything else?
More evidence that I want to bring besides a story that fits? Well, the move is called Relic Song, all the items you find in the Abyssal Ruins are "Relic" something (Relic gold, silver, copper, Relic Statue, Relic Vase). Maybe the word "Relic" is a weak proof, but I think is curious how many things link Meloetta and the Abyssal Ruins.
So, what do you think, I'm into something or I'm reaching too much?
by jojojajo12