The book in question is Baseball in the Garden of Eden: The Secret History of the Early Game, and it has been authored by John Thorn. Thorn’s name you will definitely recognize if you’re the sort of person who cared for sabermetrics before, say, the year 2000, for he authored, alongside Pete Palmer, The Hidden Game of Baseball, in which book the pair introduces linear weights (among other concepts integral to the field).
Thorn has apparently done some other things in the meantime — like, for example, consult Ken Burns on his very famous documentary about the game and also edit Base Ball: A Journal of the Early Game.
As for the present text, it appears to be a revision of baseball’s creation narrative, going beyond not only Abner Doubleday but also beyond Alexander Cartwright, too — all the way (or so this publicity material suggests) to “Daniel Lucius Adams, William Rufus Wheaton, and other fascinating figures that have accrued around baseball’s origins.”
The book goes on sale March 15th.