I'm gonna place it all here for the sake of it in case something happens to the Reddit Page:
TYPE-MOON ACE Vol. 14 - FGO Avalon le Fae ''Reminiscence''
"The Establishment of Lostbelt Britain"
B.C. 12000/Fae Era Begins
Civilization collapsed because the fairies (6 A-Rays/Sub-Bells who was tasked with forging the holy sword), didn't make the holy sword for a really trivial reason (Is it okay to skip this time?). "Is this another reset?" The fairies were optimistic about the idea, even though the surface was completely scorched.
The 6 A-Rays, barred from Avalon for neglecting their duty, emerge to the surface. Their overseer, Cernunnos (and his priestess and wife, the last human), is also with them. The fairies were baffled by the sea of nothingness they witnessed. In their distress, the fairies conspire internally, blaming Cernunnos for not making them work and ultimately deceive and murder Cernunnos... to live on top of his corpse.
"Now we don't have to float anymore!"
The helpless priestess is then made into a tool (model) for giving birth to (creating) 'humans'. It’s the birth of 'humans' in this world without reproductive functions. It’s also the start of Cernunnos’ curse and the priestess’ prophecy (one bite from an insect).
The Beginning of New Britain.
Since A-Ray is also an element that constitutes the natural world, the presence of 6 A-Rays has led to the creation of various 'offspring' that are derived from them. Under the A-Rays' leadership, various clans were formed, and the fairy society was established.
However, fairy corpses begin to float around Cernunnos. Soon, land begins to form from these corpses.
For the offspring fairies, physical death and their current generation’s death are akin to them sleeping. As long as the soul is not gravely injured, they will immediately arise as their next generation. But each time the soul experiences death, its density of existence decreases, and if the soul's injury deepens, it will not birth to a next generation and will disappear. In this period, fairies with 'Soul Scars' did not appear, and in a sense, there was peace.
B.C. 11900
The first 'Calamity'.
It wasn't just simply a disappearance of one forest (village), but rather a small-scale massacre of fairies. Since then, an epidemic of 'death' struck the fairies, causing them to perish (become Mors) simply by losing their purpose.
(The scale of this event doesn't necessarily qualify as a 'Calamity,' but because it's the root of a misfortune, it's noted as such.)
B.C. 11000
The first 'Great Calamity'.
Among the Fairies of Beginning, 2 wings (Rain and Fang) of all 6 have died out. Unlike their offspring, the 6 A-Rays are unique beings, so when one dies, their next generation does not arise. However, occasionally within the clans, a rare phenomenon known as 'atavism' (Returned A-Ray) appears, possessing power comparable to that of the progenitor.
Mirror A-Ray explains to the other A-Rays that this is Cernunnos' curse and a message from paradise:
"Admit your sins, transfer the qualifications for forging the holy sword to humans, and return to the stars (disappear)."
A-Rays and the others refuse to accept this. They claim that the surface is their land. It is a selfish statement, but it is also true that so much hard work has been done over the past 1,000 years for them to just abandon the land like that.
Henceforth, every 1000 years, a community of fairies will inevitably perish. This will then be called the land of Lostbelt Britain. Some fairies start to disappear without a next generation due to their 'Soul Scars'.
B.C. 10000
(Later) Hatred between the Wind Clan and Earth Clan surfaces.
A front-garden dispute between the Earth and Wind clans happened. Arguments over ‘sunlight rights’ escalate into a major war between the clans. Not your typical elf and dwarf squabble. Since then, they have not been on good terms with each other.
B.C. 9000
Wind and Earth A-Rays, vanished.
B.C. 8000
Mirror A-Ray, vanished.
B.C. 7000
Wing A-Ray, vanished.
B.C. 6000
The land expands, reaching all the way to present-day Scotland. It merges with the Northern fairies’ land, who have relied on Albion's corpse to survive.
'The Spring War'.
The battle concludes with the victory of the Southern fairies, who had the support of 'humans'. All of the Northern fairies are slaughtered and they uttered, "Death to the Welsh (Southern) fairies"
(Destruction of the Flame, flagged.)
Contradiction with the info released from the game:
In the game, the southern landmass first reaches Manchester before the war begins. And it's only at the end of the war that the massive amount of fairy corpses from the war cause Lostbelt Britain to expand its land into the present-day Scotland.
B.C. 5000
The Rain Clan and the Mirror Clan build their kingdoms on the site of the 'Spring War'. Founding of Orkney.
B.C. 4000
A Fairy of Paradise wash ashore in Orkney. The Rain Clan picks her up and raises her as a princess. Afterwards, the fairies kill the 'Fairy of the Lake' who came to the surface from Avalon. "Because we weren't scolded", is their reasoning.
The 'Rain fairies (one of the six original clans and lives in Orkney)' who were the only ones who tried to accept Avalon's judgment were killed by the other fairies and thrown into the Great Pit.
→Morgan from A.D. 2017, sends a fragment of her consciousness (to the best of her ability) to synchronize with the 'Fairy of the Lake'. From then on, Morgan, the 'Lostbelt's fairy vessel', becomes one with her Servant counterpart and begins to act.
The newborn Morgan embarks on a journey to save Britain. Morgan, operating under a hidden identity, is destined to be spoken of one day as a 'Witch' who purges the 'Calamity'.
※From here on, she begins to break away from the 'Lostbelt,' sucking dry its Fantasy Tree at the time for her queenship, and eventually freeing herself from the Lostbelt.
B.C. 3000
Morgan begins to be recognized as a savior. She changes her name to 'Tonelico'/'Aesc', bestowed upon her by the Rain Clan, and begins her activities.
B.C. 2000
Morgan summons Odin, the God of Wisdom, to dwell in a fairy boy who becomes the first Grimr the Sage. The first 'Fae Knight' Totorot and 'Black Knight' Ector also join the savior's party.
An invasion arrived from the 'Western Island (Irish fairies)' who want the 'Outcasts' to be expelled.
'The Summer War'.
Queen Mab, who ruthlessly exploited humans as soldiers, was incredibly greedy and powerful, but in the end, she was betrayed by her human knight, left on the brink of death, and forced into a situation where she had no choice but to agree to a truce. The Southern fairies were on the verge of extinction at the end of war.
In a way, this battle gave humanity value. (Mab was the one who wanted to liberate humans, but her successor, Knocknarea/Cnoc na Riabh, used this incident as a reason to support the faction advocating for human slavery.) Leading to a society centered around humans, treating them as slaves.
Despite being defeated, Mab ultimately accepts peace and is welcomed as one of the six clans. The King Clan is formed. However, as a punishment for the defeated, the King Clan (Mab, and later Knocknarea) was inflicted with the 'Curse of Diminished Intellect'. (Intelligence diminishes with each use of power)
As a result of this war, 'Clan System' are invented, laying the foundation for fairy civilization. The beginning of civilization is marked by utilizing human labor (imagination) of enslaved humans. This still leads to unending conflicts between clans.
Contradiction with the info released from the game:
In the game, Grimr the Sage joined Aesc on her journey to save Britain in 4000 BC.
B.C. 1000
Among the Fang Clan, a Returned A-Ray is born. The offspring with the Organs of the Planet's Exhaust Heat, Wryneck the Brave.
B.C. 800
Aesc battles and defeats the Archduke of Exhaust Heat, Wryneck. Then the two became friends.
From then on, Wryneck did not outwardly accompany Aesc on her journeys due to his position as the Fang Clan's head, but he would work behind the scenes for Aesc's sake. Although he's at odds with the mission of the Fairy of Paradise, he says he's fond of her strength. (His feelings are clear to Ector)
B.C. 400
An armed uprising by humans occurred.
'The Autumn War'.
The leader of the humans was Uther, a human knight and disciple of Aesc the Savior. This is a battle between the fairy clans, the savior, humans, and lower-ranking fairies. The humans manage to secure a situation that can be called a victory, and Uther is acknowledged as the king of New Britain.
The day before the Coronation in Londinium, the mediation ceremony...
Those in attendance were Uther, Aesc, Ector, Grimr, and the first Fae Knight/Tam Lin. Wryneck, displeased with Uther (no need to say why), does not attend the ceremony and instead heads to the west coast on the pretext of hunting Mors.
However, during the mediation ceremony with the fairies, Uther, the supposed first king of a unified Britain, was poisoned. Following by the allegations that some fairies of Londinium had been killed by humans, the fairy clans united to destroy Londinium. In addition, Aesc, who had been assisting the humans, was executed for her part in the crime. (As it is said)
On the other hand, Wryneck...
"...However, indeed. Even though a proxy was appointed, the absence of the Fang Clan’s leader is still... problematic..."
With that determination, he headed to Londinium on the morning of the coronation ceremony. When he returned, crestfallen, everything had already ended. Due to his position, Wryneck couldn't take Aesc's side, who was under condemnation by the fairies, and would agonize with this decision until the Queen Era.
"If I had been there, would anything have changed...?
...No. Nothing would have changed. Nothing at all.
As a fairy from Britain, I couldn't have saved Aesc.”
Silence falls to the ash-covered Londinium.
The first Fae Knight, Totorot, (→Galahad after the advent of Chaldea), exits to Orkney with the savior's coffin to be frozen at the base of the World Tree.
Morgan decides to use the Fantasy Tree to transform the Lostbelt into a Singularity and create a 'Faerieland'.
The 'Great Calamity' that follows will be the largest in history. →The Red Calamity
B.C. 1
The 'Great Calamity' begins and the Lostbelt ends.
The fairies are threatened with extinction by the calamity that curses them, leaving only the humans (descendants of the priestess) to survive. Some of the Northern fairies, protected by the dragon carcass in the north, have survived. Mab is also alive and well.
Originally, this Lostbelt would have 'ended' here. Afterwards, Mors and the others wander off, and the world, including the islands, gradually returns to nothingness. However, after the Great Calamity, the fairies were resurrected and reborn not as their 'next generation', but rather as their 'current generation'. This is because Morgan re-summons all the dead fairies using all of the Fantasy Tree's magical power.
※This is the decisive moment when everyone breaks free from the Lostbelt into a different world and era.
Contradiction (the last) with the info released from the game:
In the game, the first Grimr’s notes stated that there was the Calamity of the Beast, which devoured the fairies' cities, and the Calamity of the Flame, which razed everything to the ground. ...Or maybe the 'Red Calamity' is not just referring to the Destruction of the Flame, Albion but to the other one too. If that's the case, then there's no real contradiction here.
A.D. 1/Queen Era Begins
Morgan has returned from the 'World's End, Orkney'.
'The Winter War'.
Morgan's War of Conquest. She unified four of the six clans and was crowned Queen of the Fairies at Salisbury.
A Wall of Light has been formed around the island as a proof of departure from the Lostbelt.
Basic protection and rights for humans are established as part of Morgan's policies. Becoming partially aligned with Pan-Human History (as a clandestine technique unique to Morgan), some individuals from Pan-Human History are "spirited away" to Lostbelt Britain, where they are utilized as labor (imagination power) resources.
The Faerieland is rapidly becoming an 'imitation of human society'. The castle of Morgan, the Capital of Sin, Camelot, was constructed in front of the Great Pit. Under Morgan's rule, the 'reset' due to the Calamity is prevented. However, conflicts between clans have not ceased, and damages caused by Mors continues to unfold.
A.D. 400
Tensions rise once again between the Northern fairies and Camelot over the establishment of human ranches. Later, a secret agreement is formed between Mab and Morgan. Mab learns of Britain's secret, and that the resurrection (and sustenance) of all fairies is due to Morgan's summoning magic.
With that, Mab severed their ties, stating, "We part ways here. I will ensure the stability of the Northern fairies on my own".
The King Clan then builds a fortress city in the north. Queen Mab passes away. This fortress city is called the Queen City of Edinburgh, and was built from her remains.
A.D. 800
The historical relentless slaughter of the Wing Clan by the Fang Clan. The Wing Clan, except for Murian, was wiped out.
A.D. 1000
The Mors Army organized by the King of Mors, who consumes 'magical energy', have made an unusual appearance in the Faerieland.
The Great Calamity, known as Mors War, begins.
Wryneck, ready for a fight to the death against the King of Mors, said:
"Depart, King of Mors.
This is now the kingdom of the one who suffered so much to acquired it.
... I will never allow it to be taken from her again."
And so the leader of the Fang Clan falls, waiting for his 'next generation' to rise.
Following in Wryneck's footsteps, the new Archduke of Exhaust Heat is born. The Mors War comes to an end. The one who ended it was the new head of the Fang Clan, Woodwose. However, as a result, the Fang Clan falls under the Curse of the Calamity. "You guys are next." (Curse of the Beast, flagged.)
Afterwards, Black Dogs start appearing in the Faerieland.
A.D. 1100
The 'Candy Revolution' occurs in Edinburgh. From then on, Edinburgh had a monopoly on the sweets found in Faerieland.
A.D. 1300
A conflict between the Earth Clan and the Fang Clan arise. As a result, Oxford falls under the control of the Fang Clan.
A.D. 1400
A territorial dispute between the Mirror Clan and the King Clan. The Mirror clan manages to avoid major losses with the help of the Fang Clan, but their territory was greatly diminished. Around this time, Manchester falls under the control of the Fang Clan.
A.D. 1600
Aurora meets Melusine. In Norwich, Barghest of the Fang Clan is born.
A.D. 1800
'The Caterpillar War'.
Massive proliferation of caterpillar-like Mors. Morgan is in a serious pinch. (She dislikes bugs)
At the start of the war, she went out onto the plains just once, cast a massive spell on the caterpillars, and then returned to Camelot, not daring to look back. From Camelot came the official announcement stating, "The Queen humbly decided not to participate since her magic will destroy the land before it burns the caterpillars out."
Foul Weather is defeated by the Barghest and Cornwall is destroyed.
Morgan appoints Barghest as the Fae Knight Gawain. The position of 'Fae Knight' is restored. The 'Land-Eating Calamity' is eradicated through Gawain's efforts. Morgan grants Manchester to Gawain.
A.D. 1899
A shocking Battle of Manners over the 'Leadership of the Fang Clan'.
The battle was proposed by Woodwose and was supposed to be a handicap for Boggart, an idea that Woodwose came up from his arrogance. With that, Boggart desperately learns manners to compete. During the battle, Boggart puts up a good fight, and Woodwose's calculations has begun to go awry. However, Boggart at the very end, misplaced his fork after the meal, concluding with Woodwose barely edges out a victory.
'Lord of the Fang' Woodwose commented, "After all, you're just a rock-headed lion. It suits you better to simply use your bare hands".
A.D. 1870-1900
Spriggan wandered from the Pan-Human History (having been spirited away) into the Lostbelt Britain.
Around this time, Norwich begins the production of 'iron weapons'. The former Spriggan, who had not previously been involved in urban development within his territory (domain) of high mountains, has gone missing. Capless assumes the title of the second generation Spriggan and takes over Norwich.
Boggart and the craftsmen who opposed Spriggan are exiled to the north. The exiles went on to build Sheffield.
A.D. 1900
Fae Knight Lancelot, appointed. In front to her overwhelming strength, open conflicts between clans ceased.
To further strengthens Morgan's control and oppression, she increases the existence tax (boosts her magical power) and strictly limits the number of humans shipped out from the ranches.
The 'Calamity of Resurrection' in Darlington occurred.
Lord Grimalkin, vanished. As her soul vanished too, there was no 'next generation' of her that emerged.
Morgan discovers the reincarnation of Baobhan Sith and offered her protection. However, she now lost her name (purpose) and her soul is already exhausted so another reincarnation is impossible. Thus, the both alive and dead (living dead) Baobhan Sith, awakes as the queen's daughter.
Fae Knight Tristan, appointed. The City of Pleasure, New Darlington, was constructed with her as the Lord.
Knocknarea is born in Edinburgh. She's a Great Fairy who possessed abilities equivalent to the Fairies of Paradise. She continued to live by consuming approximately 1500 years’ worth of magical essence from the gathered corpses of Northern fairies and Edinburgh's immigrants.
A.D. 1999
In a certain dumpsite, a representative of the island of Britain is born.
A.D. 2001
King’s Prophecy.
Altria emerges in the Lake Region and was sheltered by the Mirror Clan. However, knowing that eventually the Mirror Clan would be wiped out (by Aurora), Ainsel cast Altria adrift into the sea. Later, Altria washed ashore on the cape of Tintagel.
Percival (shipped at a young age), at the age of one, is purchased by an orphanage.
A.D. 2011
City of the Mirror Clan, destroyed by Mors (in truth, by Melusine).
Percival uses the Spear of Selection for the first time.
A.D. 2012
Camelot hosts an Imperial Tournament (Round-Robin Tournament). After an audience with Morgan, Percival resolves to strengthen himself and form a rebel army.
A.D. 2012-2015?
Oberon proclaims himself as the Faerie King of a fairy kingdom in the 'Forest of Wales'. The fairies dismissed him as just a jester, a brash and boastful fairy, but all of those who met him grew fond of him, and his title of Faerie King was never ridiculed again.
A.D. 2015
Gawain arrives at Ector's forge. Altria nearly got into a one-sided argument with her for not noticing the little girl.
A.D. 2016
With the help of Oberon, the Round Table Army is formed in Londinium.
A.D. 2017
The emergence of Fantasy Trees on the blank Earth.
Beryl is dispatched to the British Lostbelt. It was a land of barren wilderness and black ghosts. Then the next day after he summons Morgan, Britain's situation changes dramatically.
When summoned, Morgan instantly grasped the system of the Lostbelt and Rayshift to send information to the 'Fairy of the Lake' who existed 6000 years in the past, and then died. Upon receiving the information, the 'Fairy of the Lake' took it upon herself to raise the Lostbelt Britain as Morgan, and change Britain’s fate of being a Lostbelt. When the Fantasy Tree burned out in the first year of the Queen Era, Britain changed from Lostbelt to Singularity as a 'Faerieland'.
The Morgan encountered the day after Beryl's summoning is no longer Beryl's servant, and her appearance has also changed to that of the queen. The situation on the island has completely changed, with a Wall of Light visible on the outside and a withered Fantasy Tree, already devoid of substance, looms on the horizon.
"I devoured the contents while you were asleep," said Morgan to Beryl.
The truth is, it had withered away 2000 years ago.
In response to the legend of the "Child of Prophecy," the previously 'in low-gear' human organization becomes more active.
Altria Caster’s Day of Departure. 
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