Not sure of any "factual" books, but as excellent reading (WBTS) fiction, one of the best I've ever read was "Lone Star Preacher" by John W. Thomason. Thomason was a Marine officer who served in WWI, on the old "China Station" between the wars and died of natural causes in WWII while still on active duty. He was also a short story writer of some renown in the 1920s-30s and if I remember correctly, "Lone Star Preacher" was a collection of his short stories originally published in the old "Saturday Eveing Post."

The hero, the Reverend Praxatillis Swan, Methodist-Episcopal Church, South, goes off to war with Hood's Texas Brigade in Virgina, initially as regimental chaplin, and becomes a 'fighting preacher' with the company from his home town. Some of the greatest "grunt-level" descriptions of battle I've read.

I have misplaced my copy, but it was republished several years ago...I think possibly by the University of Texas Press...if interested any of the "big box" book stores can check on its current availability.