Warlock Grimoire Hardcover for 5th Edition - Rules of Play says:

The Warlock Grimoire presents the content from the first ten issues of Warlock and includes an entire issue’s worth of new, never-before-seen lore and game elements, detailing life in the Ironcrags, recent events along the west coast of the Wasted West, the dedication and intensity of Perunalian archers, and the holy drive of the paladins of the Sun God.