John Buchan 
Prester John [EPUB ebook] 

Nineteen-year-old David Crawfurd travels from Scotland to South Africa to work as a storekeeper. On the voyage he encounters again John Laputa, the celebrated Zulu minister, of whom he has strange memories. In his remote store David finds himself with the key to a massive uprising led by the minister, who has taken the title of the mythical priest-king, Prester John. David’s courage and his understanding of this man take him to the heart of the uprising, a secret cave in the Rooirand.