These are three of Haggard's African Novels, which are temporaly far apart in Quatermain's life, but united by being stages of the downfall of the Zulu nation and the destruction of the Chaka dynasty brought about by the wizard Zikali. If you like Haggard's african adventures, you will probably also like these, and recognize some figures, but there is a bit less exoticism and more real politics and history in them. No unknown tribes, mythical monsters or inaccessible places, only the hunter and trader Quatermain getting drawn into Zulu affairs, and Zikali working some miracular oracles and signs, and giving most calculated bad advice.
The book itself is ok, only the printing is a bit dense and small, it feels a bit unpleasant to read, but one gets used to it.