The Hunger Saint is about Ntoni, a twelve-year-old boy forced to labor in Sicily’s sulfur mines to support his family after his father’s untimely death. These child laborers were called carusu or “mine-boy”, a labourer in a sulfur mine who worked next to a picuneri or pick-man, and carried raw ore from deep in the mine to the surface.
For more information about the carusu check out wikipedia or this youtube video
This was recent enough that there are still living people who lived in these conditions. Sure this is a fictionalize book, but the history is real