The following is a transcription of the intro: Like in its predecessors, the story and lore of Dark Souls 3 can be pieced together through its introductory cinematic, item descriptions, dialogues, and environments.
The five Lords of Cinder are Ludleth the Exiled Aldrich, Saint of the Deep Farron's Undead Legion, the Abyss Watchers the reclusive lord of the Profaned Capital, Yhorm the Giant and Holy King Lothric, Last Hope of His Line. Lords of Cinder are past beings who were successful in linking the flame, being burned remnants of their past selves. The protagonist is known as an Unkindled, a kind of Undead, although it is never fully enunciated upon what differentiates an Unkindled from other Undead. There are implications that an Unkindled is the remains of an Undead warrior who failed to link the flame and, as a result, burned their bodies into ash. You play as a protagonist whose goal is to find and return the five Lords of Cinder to their thrones at Firelink Shrine in order to link the flame again. Dark Souls 3 takes place in a transitory place, revolving around the first flame and the cycle of fire and dark.