Age of Ancients - A colorless world enshrouded by fog, ruled by the Everlasting Dragons.
The First Flame - Four beings find power within the First Flame, the Souls of Life, Death, Light, and Dark, each respectively held by the Witch of Izalith, Gravelord Nito, Lord Gwyn, and the Pygmy.
The Divine’s War - Lord Gwyn wages war against the Everlasting Dragons, and finds an ally in that of the scaleless Seath. The Divines win their bid for dominance, and push the Dragons to near extinction.
Humanity’s Source - The Pygmy shatters his soul sometime in between the war and the Age of Fire, giving spawn to the ever fickle Humans. Likely during, given Havel’s status as a wartime friend to Lord Gwyn.
The Age of Fire - An age of peace and prosperity. Seath is rewarded for his assistance in the war and is recognized in dukedom, welcomed by the royalty, and is even given a part of Gwyn’s soul. Humanity flourishes under the rule of the Divines, and establish a city under their gods - New Londo. Lord Gwyn bequeaths a part of his soul to the Four Kings, recognizing their foresight. Humanity spreads across the land, establishing even more colonies such as the forests of Oolacile, the adventurous Zena, the warrior-nations of Balder, Berenike, and Catarina, the zealous lands of Thorolund and Carim, and the kingdom of Astora.
The Four Knights - Between the events of the war against the Ancients and the Age of Fire, Gwyn appoints four individuals to guard the realm from those who would threaten it. They are Ornstein the Lion, slayer of dragons; Gough the Hawk, whose mighty arrows are faithful to their mark; Ciaran the Hornet, who strikes fear from the shadows; and Artorias the Wolf, the indomitable master of sword and shield.
Fall of Izalith - The Witch of Izalith fails an attempt to recreate the First Flame, and becomes the Bitch I mean Bed of Chaos, the source of all demons, Izalith itself lost to this spread of chaos. Several of the Witch’s daughters and her only son are heavily affected by the initial invocation, and scatter to the winds. Gwyn sends a special detachment of knights to quell the ever-growing presence of demons, their charred armors granting the moniker “the Black Knights.”
Reduced to Embers / Gwyn’s Sacrifice - With the dwindling essence of the First Flame, the rising power of the demons, and perhaps forseeing the chaos of the Undead Curse and power of the Abyss, Gwyn realizes that the power of the First Flame is needed, now more than ever - and so he kindles the flame with his own soul, so that he might further delay the destruction of the realm. Before his journey to the Kiln, Gwyn bequeaths most of his power to his family, but yet remains with a powerful soul.
The Undead Curse - In correlation with the dying First Flame, certain humans become branded with the darksign and become undying, and suffer negative psychological tolls after numerous “deaths” eventually becoming “Hollow,” a term in which a human has fully (and likely irreversibly) lost their sanity.
Havel’s Coup - Archbishop Havel, a friend to Lord Gwyn and sworn enemy to Seath, mutinies against his former comrades with the power of occult, and fails, hollowing in the process. Though there is no definitive source of when exactly Havel would attempt his betrayal, it is at least sometime after the appearance of the Curse, likely during the height of the matters when the Divines and Seath were most vulnerable.
Abandoning the Light - With Lord Gwyn gone and the power of the First Flame now weaning by the second, the Divines abandon Anor Londo and likely all of Lordran itself, desperate to escape the Dark that knocks on the city gates. Few Divines remain, among them are Gwyndolin, who devises the illusions of Anor Londo in an attempt to grant a false pretense of Divine authority. Executioner Smough and Knight Ornstein also remain to protect Gwynevere’s illusion and the Lordvessel.
Fall of Balder - Balder is lost not long after the outbreak of the undead curse.
The Art of Lifedrain / Fall of New Londo - The crowns of New Londo are offered the art of Lifedrain, a powerful art that allows one to siphon the humanity of other humans, by a not-so-mysterious serpent. The Four Kings remedy their curse with this art – at a cost – and corrupt the knights under their rule, forming the Darkwraiths, their fall to dark allowing the Abyss to further taint it’s borders. The sorcerers Ingward, Yulva, and an unnamed third sink the keep in order to contain the art of Lifedrain, and are from thereon known as Sealers. Sometime during or after the Fall of New Londo, Artorias swears a covenant to the beasts of the Abyss (likely Frampt) in order to combat Darkwraiths in their element. It is stated that he hunted Darkwraiths, but it is uncertain if he was present during New Londo’s dissolution, meaning he may have actively tried to liberate New Londo from the Four Kings, but subsequently failed before it’s inevitable flooding. (Artorias’ covenant to the Abyss being a result either way - he may have used it in an attempt to reach the Four Kings, but ultimately uses it to hunt any Darkwraith)
Fall of Oolacile - The residents of Oolacile unearth the primeval progenitor of humans, Manus, colloquially known as the Father of the Abyss. Manus’ uncontrolled humanity mutates the residents of Oolacile, and decimates the land. Princess Dusk is abducted, and Marvelous Chester is pulled from the future.
The Legend of Artorias - Artorias is summoned once again, believed to be suited to the task during his endeavors against the Darkwraiths - however, the raw form of Manus’ taint proves to be too powerful for the lesser divine. With his arm asunder, Artorias makes use of his shield to protect his companion Sif, before falling to the Abyss. The Chosen Undead is pulled from the future holding a piece of Manus’ amulet, who then lays the spirit of Artorias to rest, fells the Black Dragon Kalameet, and later, defeats Manus, stopping the spread of his Abyss, but effectively shatters his power, the repercussions of which would take ages to take form.
The Chosen’s feats are accredited to Artorias, honoring the fallen knight.
Vinheim, Dragon School of Sorcery - Dusk’s dialogue suggests the more aggressive “modern” forms of sorceries did not exist during Oolacile’s reign, meaning that Vinheim’s studies were performed sometime after Oolacile was lost along with the original arts.
Thorolund’s Undead Hunts - Allfather Lloyd’s cleric knights of the way of white deem the undead as “accursed creatures” and begin hunting them without mercy. They are corralled to a remote location called the Undead Asylum, and given little hope of escape.
Oscar’s Prophecy / Fate of the Undead - Oscar speaks of a prophecy where undead are destined to journey to Lordran, to ring the bells of Awakening and learn the truth of the Undead.
The Chosen’s Path - A fated undead, whom makes pilgrimage to the land of ancient lords in search of purpose. It is worthy to note that a considerable amount of time has passed since Gwyn’s sacrifice (Quelana makes mention of a thousand years since her mother had failed to recreate the First), and many Undead have pursued the prophecy, such as Knight King Rendal of Balder, and Black Iron Tarkus of Berenike, and have since failed to surmount the challenges of Lordran. Following the words of a hollowing knight, the undead rings the bells of awakening and is then tasked by Kingseeker Frampt, a primordial serpent, to collect the Lordvessel and souls of the former Witch of Izalith, Gravelord Nito, and the bequeathed shards of the white dragon Seath and the lost Four Kings. Along this journey the Chosen might meet Darkstalker Kaathe, counterpart to Frampt, who opines the prophecy as false, and instead suggests the undead to allow the First Flame to whither and usher in an age of Dark and Man.
Extended Age of Fire - Should the player choose to do so, the First Flame is kindled by the player character’s powerful soul, burning for a considerable amount of time, and assumedly lifts the curse of the undead for a temporary time.
Age of Dark / Age of Man - Regardless of the player’s choice, the First is destined to fade. Now with the Divines powerless, the Demons of Izalith quelled, and the Abyss stalled, humanity is left to it’s own machinations.