I am bored at work, and have some time to kill, so I figured i'd write some bullshit. None of this matters, don't bother reading it unless you too are bored.
Previously in this thread I said that I thought that DS2 was the future in which the flames are linked in DS1 and that DS3 is like the alternate reality in which the protag chose the dark lord ending. The basis for this was because DS 2 seems to continue on with the undead curse and the cycle seems to just keep moving on where-as everything in DS3 seems like some kind of doomsday scenario where it's all going to shit, and the true end is nigh.
I think I was thinking backwards.
I never really accepted the idea of there being a cohesive plot in the background. I don't even think From has a true master-doc of it all written out and are only choosing to share parts for the sake of the experience. I honestly think they just come up with some neat/cool/tragic ideas and intersparse them throughout the games, leaving the fans to squint really hard to see the lines between them. They do have some very cool themes tho. DS 1 had the idea of one's sanity and humanity being dependent on working toward a goal, and that once that goal was met or failed that the person would lose themselves indefinitely. Righteous and upright people like Laurentius and Siegmeyer have tragic ends, where-as nihilists like Patches are nearly immune to that problem. In DS 2, memory and sense of self and direction is slowly slipping with everyone kind of forgetting who and what they are, why they're here -- they just know that they have to survive somehow and are trying to keep moving forward. There's no tragic ending here, because the very story itself doesn't lean to that -- the game tells you, you're never going to know why, really, and you don't -- you just keep going until you are on top, sitting on the throne (which is ironically underground.)
Anyway, the themes also kind of cover different entities. DS 1 and 3 are about the gods or otherwordly beings that more or less run the world. Where-as DS 2 is about kings and duty. The linking of the flame is a scam to keep the status quo -- returning the lords to their thrones in 3 is almost like some kind of caretaker being pulled in to find senile elders. The whole system, from ground up, is designed to cannibalize the young and the new for the sake of the old. Humanity is treated as a disposable means to an end for the flawed system of those in power to remain in power. DS 2 on the other hand is the only game in the series that specifically involves the older generations sacrificing themselves for the sake of the newer ones. Vendrick couldn't quite cut it to be the True Monarch for reasons never fully divulged, other than the giant invasion and his own treacherous Manus-Spawn wife. However, he didn't ruin things for those who came after, he instead hid whatever hope he could muster (his ring, which gave access to the giant's kinship) so that the next champion, through him, would finish the task he was unable. Likewise, the other kings in the DLCs, all tried to achieve greatness in human empires but failed in some capacity. Some were directly defeated (sunken), some gave to corruption (iron), and some held true to the bitter end and fought the darkness until it devoured them (ivory, in parallel to artorias.) Here the emphasis is on duty as mirrored by the two primary roles of monarchs and the knights who serve them. Even the maiden is loyal to you, pledging to stand by you always. This is definitely a more human story, and I think DS 2 is likely what would happen if the original chosen undead became the dark lord and forsaked the "gods". The gods themselves not being omnipotent deities like in the christian sense, but more like greek gods who are superhuman but not infallible.
The real truth, is that that's all garbage and the game is just some minor themes cobbled together with recurring concepts of the cycle, linking the fire, etc. There's nothing more than what the designers thought would be cool at whatever time, and people can just read into it very easily because of how vague and ambiguous it all is -- like astrology/horoscopes