"Kaptajnen paa 15 Aar (I Slavelænker)" by Jules Verne is a novel published in 1878. When a whaling voyage goes disastrously wrong, fifteen-year-old Dick Sand finds himself commanding a ship with no experienced crew. Manipulated by a treacherous cook, the vessel is secretly diverted to Africa instead of South America. What begins as a navigation error becomes a harrowing struggle for survival as Dick and his passengers—including a woman, her young son, and African survivors—fall into the hands of slave traders in Angola's brutal interior.
Abridged translation of "Un capitaine de quinze ans." Wikipedia page about this book: en.wikipedia.org/wiki/Dick_Sand,_A_Captain_at_Fifteen