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The Deep Ones are believed to be an ancient race of half men, half fish. They supposedly built the Seastone Chair on the Iron Islands, and some readers suspect they also built various other structures — the carved oily/greasy stones — around the world.

There is also evidence of their interbreeding with humans, as people in disparate locations bear physical characteristics reminiscent of fish-like creatures, with webbed hands and feet, green-tinged skin, and other odd traits.

There is tons more textual evidence supporting their existence, but that is ultimately not what this post is about.

I believe they existed for a singular purpose, bred with one goal in mind.

Before I get to what that purpose was, here is a refresher on the Deep Ones, the primary paragraph from The World of Ice and Fire:

…a queer, misshapen race of half men sired by creatures of the salt seas upon human women. These Deep Ones, as he names them, are the seed from which our legends of merlings have grown, he argues, whilst their terrible fathers are the truth behind the Drowned God of the ironborn. The Reach: Oldtown, TWoIaF

They were sired, and their fathers were the creatures of the sea who also inspired the religion of the Drowned God. So they were not some race that sprouted naturally, so to speak: they only existed because their fathers thought to copulate with human women.

For what purpose, however?

I believe they were bred for the sole purpose of destroying the mazemakers, a race of half-giants:

The mazemakers left no written records, so we shall never know. Their bones tell us that they were massively built and larger than men, though not so large as giants. Some have suggested that mayhaps the mazemakers were born of interbreeding between human men and giant women. We do not known why they disappeared, though Lorathi legend suggests they were destroyed by an enemy from the sea: merlings in some versions of the tale, selkies and walrus-men in others… The Free Cities: Lorath, TWoIaF

Legends suggest the mazemakers were annihilated by enemies from the sea, merlings in some tales, yet the Deep Ones inspired the legend of merlings:

These Deep Ones, as he names them, are the seed from which our legends of merlings have grown… … they were destroyed by an enemy from the sea: merlings in some versions of the tale…

Why do I believe that was the purpose of the Deep Ones, however?

Because of who their fathers really were. Their true identities, if I am correct, would tell us much and more. Their fathers are the main subject of this post.

The Suspects – Who and How?

Let us read again of those that spawned the Deep Ones:

…a queer, misshapen race of half men sired by creatures of the salt seas upon human women.

Sea creatures… what would they want with humans? How could such beasts have any motives at all beyond their biological imperatives?

Perhaps they were not just simple creatures, you could say; perhaps they possessed some level of consciousness and therefore their own motives. Or you could even believe they were just beasts whose carnal instincts took over one day, leading them to breed with human women, no ulterior motive behind it.

But there is a better answer, in my opinion, one that would explain it all well enough. It is an answer hinted at throughout the books from the very beginning:

“Old Nan says the children knew the songs of the trees, that they could fly like birds and swim like fish and talk to the animals,” Bran said. Bran VII, AGoT “Supposedly the greenseers also had the power over the beasts of the wood and the birds in the trees. Even fish.” Maester Luwin, Bran IV, ACoK “The greenseers were more than that. They were wargs as well, as you are, and the greatest of them could wear the skins of any beast that flies or swims or crawls…” Jojen Reed, Bran I, ASoS

I believe the fathers of the Deep Ones were none other than the children of the forest – wearing the skins of sea creatures, of course.

Sounds funny, doesn’t it? It’s easy to forget, however, that “children of the forest” is a total misnomer. In fact, they actually call themselves singers, those who sing the song of earth:

“The First Men named us children,” the little woman said. “The giants called us woh dak nag gran, the squirrel people… but we are no squirrels, no children. Our name in the True Tongue means those who sing the song of earth.” Leaf, Bran II, ADwD

Either way, you don’t have to accept this whole supposition right away; in fact, I would say to hold off on that as I have yet to even present the motive. So, for now, let me pose a question instead:

If the fathers of the Deep Ones were only sea-dwelling beasts, what would be the best way to acquire human women?

Just food for thought. Yet whether they were singers wearing the skins of sea creatures or not, the books may yet again provide an answer.

Because why bother looking for humans when someone conveniently serves them to you on a platter?

The old songs say that the greenseers used dark magics to make the seas rise and sweep away the land, shattering the Arm, but it was too late to close the door. Maester Luwin, Bran VII, AGoT And then the seas came rushing in, and the Arm of Dorne was broken and shattered by the force of the water, until only a few bare rocky islands remained above the waves. … Even if we accept that the old gods broke the Arm of Dorne with the Hammer of the Waters, as the legends claim, the greenseers sang their song too late. Dorne: The Breaking, TWoIaF

Invoking the Hammer of the Waters, the singers drowned the land, and men along with it – women too, of course, for the First Men came with their women:

… for the women of the First Men brought forth sons and daughters with much greater frequency than the females of the elder races. Dorne: The Breaking, TWoIaF

Would they really have drowned along with the land though? Was the Hammer of the Waters a cataclysm that could strike so quickly?

Well, the official Game of Thrones History & Lore seems to imply so. The video even depicts a singer hanging onto a tree, watching below while men drown, surrounded by fishes.

Even so, water magic has been effectively used throughout history to specifically drown men:

Art and music flourished in the cities of the Rhoyne, and it is said their people had their own magic—a water magic very different from the sorceries of Valyria… …their cities were protected by “watery walls” that would rise to drown any foe. Rhoynish water wizards called up the power of the river and flooded Volon Therys. Ancient History: Ten Thousand Ships, TWoIaF

So perhaps human women were given to the creatures of the sea to bring forth the Deep Ones. I am not saying that was the actual, intended purpose of the Hammer of the Waters; I am only saying that drowning whole lands replete with humans would be the best way for these sea creatures to be served human women.

After all, the Arm of Dorne is not the only land that has sunken into the sea:

…the great floods that broke the land bridge that is now the Broken Arm and made the Neck a swamp were the work of the greenseers, who gathered at Moat Cailin to work dark magic. … What became of Valyria is well-known, and in the Iron Islands, the castle of Pyke sits on stacks of stone that were once part of the greater island before segments of it crumbled into the sea. Ancient History: The Coming of First Men, TWoIaF

(There are also the Thousand Islands, but I will get to them later.)

The Iron Islands and Valyria sank into the sea as well. Whether they were also the work of the singers is obviously up for debate, but that is not why I brought them up.

When the Doom of Valyria happened, thousands of people inhabiting a nearby island drowned as well:

On the day the Doom came to Valyria, it was said, a wall of water three hundred feet high had descended on the island, drowning hundreds of thousands of men, women, and children … the hills and valleys beneath them turn into a raging sea. The Iron Suitor, ADwD

This is in Victarion’s POV chapter, and he has an interesting thought after recalling this tale:

So many drowned men, the Drowned God will be strong there, Victarion had thought.

The Drowned God is strong where men have drowned, the Ironborn believe.

By that logic, the singers made the Drowned God strong by drowning men at the Arm of Dorne. However, the Drowned God is inspired by real beings who fathered the Deep Ones…

… whilst their terrible fathers are the truth behind the Drowned God of the ironborn.

… so could this notion of empowerment be rooted in some reality and not just religious belief?

I believe so.

Logically, if thousands of humans, women included, were cast into the waters by the sinking of the land, then it would undoubtedly be easier for creatures of the sea to impregnate human women and sire half-human, half-fish beings – the Deep Ones.

With that taken into consideration, the fathers are made stronger, as they are able to spawn more brood to do their bidding.

Finally, since my theory postulates that the singers were actually wearing the skins of those sea creatures, it paints a more complete picture, one of coordination and orchestration:

The singers sunk whole lands into the sea, along with humans, while their greenseers, wearing the skins of creatures of the salt seas, took their women to breed.

But if the Drowned God is/was a greenseer(s), is there any text that might point to this?

While spending a night sleeping on that drowned isle caused by the Doom of Valyria, Victarion Greyjoy has horrible nightmares, a sign he took from the Drowned God:

He did not like this Isle of Cedars either. … The last time Victarion had spent a night ashore, his dreams had been dark and disturbing and when he woke his mouth was full of blood. The maester said he had bitten his own tongue in his sleep, but he took it for a sign from the Drowned God… The Iron Suitor, ADwD

Remember that the Drowned God is inspired by the fathers of the Deep Ones, so if the fathers were in fact greenseers, then they would also possess the ability to visit humans in dreams:

“I have been many things, Bran. Now I am as you see me, and now you will understand why I could not come to you … except in dreams.” Bloodraven the last greenseer, Bran II, ADwD

So let us say, one greenseer, a being with god-like powers, chose to stay dwelling under the waters wearing a sea creature’s skin. Let us say, figuratively, that this god drowned, then.

Do you know what Bloodraven the last greenseer told Bran about being outside his skin for too long? It was in the show, and it was a metaphor, yet it was quite a curious one:

“It is beautiful beneath the sea, but if you stay too long, you’ll drown.“ The three-eyed raven, A Game of Thrones Season 6, Episode 2

Yet was the Drowned God not always drowned?

Aeron Greyjoy, the most pious priest of the religion, seems to believe so:

“Lord God who drowned for us,” the priest prayed, in a voice as deep as the sea, “let Emmond your servant be reborn from the sea, as you were.” The Prophet, AFFC

The god of the Ironborn drowned for them, they believe. Yet the fathers of the Deep Ones are the truth behind the Drowned God, and they were creatures of the salt seas.

So how could this myth in their religion have come about? How could sea creatures drown?

Perhaps they were not truly sea creatures, but greenseers – skinchangers – whom found it beautiful beneath the sea, and they stayed too long they drowned.

I don’t mean to say that they perished – I mean to say that they stayed, as creatures of the sea. Maybe they still retain their powers, and maybe there is only one of them left. Maybe their real bodies linger in the deep dark sea, entangled in seaweeds, preserved like Bloodraven in his tangle of weirwood roots.

Note: Even without the line from Bloodraven in the show, book canon establishes that skinchangers often lose themselves in their beasts, preferring to live as their animals instead. I am merely suggesting the same of sea skinchangers.

Motive: Part I – Why?

All I have presented thus far would mean nothing if there was no logical motive for the singers to do what I purport that they did.

To understand their motive for fathering the Deep Ones, we must understand the ones they vanquished: the mazemakers.

First off, remember the mazemakers were giants, or at least half-giants:

The mazemakers left no written records, so we shall never know. Their bones tell us that they were massively built and larger than men, though not so large as giants. Some have suggested that mayhaps the mazemakers were born of interbreeding between human men and giant women.

Since time immemorial, giants and singers waged endless war against each other; they were great foes:

…their greatest foes were the giants, as hinted at in tales told in the North, and as possibly proved by Maester Kennet in the study of a barrow near the Long Lake—a giant’s burial with obsidian arrowheads found amidst the extant ribs. Ancient History: The Dawn Age, TWoIaF

And some words from the singer Leaf:

“The giants are almost gone as well, they who were our bane and our brothers.” Bran III, ADwD

So they were arch enemies, once: the singers and the giants — and the mazemakers were literal half-giants. Thus, it only makes sense the singers extended their antagonism to the mazemakers.

But before delving deeper into their relationship, allow me to address one question you may have:

Are there any hints the mazemakers were ever in Westeros?

I believe there are. More specifically, I believe they left a trail in Essos that ultimately leads to Westeros.

The Old Ones

To start off, we know the mazemakers were capable of leaving their island, as one of their mazes is found on Essos proper:

… the mazemakers’ constructions are scattered across the isles—and one, badly overgrown and sunk deep into the earth, has been found on Essos proper, on the peninsula south of Lorath. The Free Cities: Lorath, TWoIaF

And faraway on another island off the coast of southern Essos sits the isle of Leng, home to abandoned cities, remnant of some vanished people:

No man can say who might have built these cities, or when. They remain perhaps the only remnant of some vanished people. The Bones and Beyond: Leng, TWoIaF

These vanished people who built these cities were likely the Old Ones of that same isle:

… the Old Ones, gods who lived deep below the ruined subterranean cities… The Bones and Beyond: Leng, TWoIaF

They built massive buildings and labyrinths of tunnels that lead underground: