For readers interested in 19th-century American history, the American Civil War or war records:
Federico Fernández-Cavada was, according to his Wikipedia page, a Cuban-born officer in the Union Army during the American Civil War. He was captured at Gettysburg and was held at Libby Prison. His book Libby Life: Experiences of a Prisoner of War in Richmond, Va., 1863-64 (1864) records his time there.
The author's Wikipedia page:
https://en.wikipedia.org/wiki/Federico_Fern%C3%A1ndez_Cavada
The title page of Libby Life:
https://archive.org/details/libbylifeexperi00cavagoog/page/n8/mode/2up