Book of Alma
From MormonWiki
The Book of Alma is the ninth and longest book of the Book of Mormon containing sixty three chapters. The principle author of the book was Alma the Younger, from whom it gets its name. The account which commences in 91 bc concludes in 52 bc, a total of 39 years.
Aside from its being long, the Book of Alma is also well known for its account of wars between the Lamanites and Nephites.