in the age of ancients, badically at the beginning of everything, the land was unformed, gray, and filled with fog, and the world only had the Everlasting Dragons, who were basically inmortal as their scales made out of stone basically protected them against literally anything, but there was one dragon without these scales, The Scaleless, a dragon that was doomed to die from the very beginning, we'll get back to that dragon later.

there was also a primordial race of serpents hidden away which only turn important a bit later on so we'll ignore them for a bit

far, FAR deep underground, fire begins sprrading, from which They arrive, hollowed, mindless.

four of them actually found 4 souls between the fire, the so called Souls of The Lords, and with no better thing to do, they decided to absorb the souls to see if they do anything.

Nito, finds the death soul, and basically becomes the grim reaper of dark souls

The Witch of Izalith, finds the life soul, and splits the power of this soul between a few other hollowed, becoming her daughters, and also learning pyromancy for some reason i forgot sorry

Gwyn, finds the soul of light, the strongest one, which lets him absorb the very power of the sun, and transforms some of the hollowed into his faithful knights. And the Furtive Pygmy, finds the dark soul.

Gwyn, the Witch of Izalith, and Nito buddy up to challenge the everlasting dragons on an epic fight, gwyn summons his rays of sunlight which pierce through their dragon scales, the witch of izalith and her daughters set them ablaze, and nito deals the final blow, summoning a miasma of death and disease. and Seath, the Scaleless, betrayed his own kind at a chance to develop inmortality.

And thus, the dragons were long gone.

Then began the Age of Fire, and humanity started to spread.

Gwyn became a deity, had many sons, and actually gave a fragment of his soul of light to the MVPs of the fight against the dragon, we only know of 2 people that got these fragments, seath and the Four Kings of New Londo, that, well, went on to fucking rule new londo with their newfound powers!

There was also havel, which didnt really get a fragment of gwyns soul, but he became a semi deity dud to his SHEER. FUCKING. STRENGTH. he wore an entire set of armor made out of fucking solid rock, and his weapon was the tooth of a dragon he slain, which, conveniently was also made out of rock, and so men admired him and wanted to get armor like that, to which they created the Havel Ring, which made them able to actually wield shit like havel and turned into the Havel Knights, however it would not be fucking called dark souls if it ended this way.

Seath, on his research of inmortality, created sorcery as a byproduct, havel was hating on him because of that and basically created a whole ass magic barrier to counter and fuck up sorcery, to which the lords locked him up due to him being a crazy ass, place where he would eventually develop the Darksign and become hollowed, but we'll get to that later.

Seath's reaearch also drives him insane, and makes him do way more fucked up experiments and he begins to kidnap people to experiment on, so gwyn locks him up on his own library due to being a crazy ass.

Something is happening to the Four Kings, they began to conspire against gwyn using the art of lifedrain, taught to them by the primordial serpent, kaathe.

remember the primordial serpents? one of them, frampt, becomes besties with gwyn at some point, both of them will come back later.

due to the four kings rebelling, gwyn decides to flood the entirety of new fucking londo, killing thousands of people in the act, and basically trapping the four kings in the abyss, where they go insane.

the power of the first flame, the very one that they owe their existence to, begins to fade as well, gwyn implores to the witch of izalith to try and use her pyromancy to keep the flame alive, however this was a shit mockery of the flame, which basically released hell upon the world and demons started to appear, and the witch's daughters also became demons, and the witch herself got destroyed and turn into a tiny little bug/tree. gwyn tries to combat these demons, creating the Black Knights, knights with armor and weaponry specifically made to slay demons. some actually still appear during the game too

remember the furtive pygmy? owner of the dark soul? all of this time he has actually been splitting the power of it with random people he found, until it eventually wasnt strong enough to keep him alive and he fucking died.

however, the dark soul also released the curse of the undead, the Darksign.

basically if you have the darksign you cannot die but youll turn into a hollow, lifeless, mindless shell of a body and go insane.

in a last attempt for gwyn to help, he sacrifices his soul to link the first flame and keep the age of fire going, and prolonging the age of darkness, hopefully long enough for the remaining lords to find a solution to everything.

meanwhile, the people with the darksign curse are grouped up, and led to the north to an undead asylum, where they shall rot away, a demon takes over this place eventually as well

soon the lords realize they really cant stop it at this point so they create a prophecy that one day, one undead shall escape the asylum on pilgrimage to anor londo, the land of the lords, to undo the curse and save the world, basically to sacrifice themselves to the flame so that the age of fire goes on again, the primordial serpent krampt assists by going on a quest to find humans to do so, while kaathe stsys in the abyss with the four kings of fucking nothing anymore.

this is where your character comes in, youre the chosen undead, the one that shall undo the curse, you meet some people along the way too, but as you go on with their quest they either die indirectly because of you or something really bad happens to them, because of you.

you are tasked to slay seath, nito, the four kings, and whats left of the witch of izalith, so that you may have a soul power strong enough to face gwyn and be able to "undo the curse"

you find seath, to discover that he never found the key to inmortality.

you find the four kings, to find out their entire kingdom went away, and replaced with ghosts.

you find the witch of izalith, now just a Bed of Chaos, an insignificant bug you can kill in one hit.

and honestly nito is just chilling nothing really happens to him

once you do, you face gwyn on your last (and probably saddest) fight, and then youre met with 2 options, you can either link the fire, or let it die and begin the age of dark, and become the dark lord, but the thing is, neither of these endings is the good one.

if you link the fire youre basically prolonging the inevitable, but if you become the dark lord, youd think that you start the age of humanity at first, but humans cannot live in the dark, because the very reason of their existence is owed to the fire.

but yeah i really abridged this theres way more