Board Thread:Lore Discussion/@comment-16355664-20140327203553/@comment-24684538-20140402032624

I don't think Vendrick is the Chosen Undead from DkS1 but I do think he was a Chosen Undead from a different cycle. As for the Four Great Ones, I don't think it is Gwyn, Seathe, Nito and Witch of Izalith but I do think it is four people/things with their souls, since the Lords found their souls (so they weren't born with them) it is possible that others found the same souls (this is heavily implied in NG+) and the souls possibly retain their power and memories/experiences which could lead to events similar to the events of DkS1; e.g. A king that is consumed by fire, a woman that recreates the Flame etc.

Vendrick may have been the Chosen Undead before your character in DkS2 and instead of linking the Flame or becoming the Dark Lord, he may have been searching for an alternative method (or possibly ignoring the responsibility) in order to stop Nashandra.