I've read about half of the lore book (I think).
The chapter about the origin characters is just their backstory, no actual spoiler really. When you play as them or hire them as companions they'll tell you about it anyway. At the end of this chapter the book also describes I think two or three more characters, but since I haven't yet seen or heard about them in the game (still in Act 1), I consider that part "spoilerish".
Everything before that part is, for me at least, not spoilers, because they describe things that happened in the past (events in some of the past divinity games).
Last edited by Feoras; 03/10/17 04:31 AM.