Umslopogaas was a Zulu chief, Allan Quatermain's brave and noble companion.
In 1886 Allan having persuaded Sir Henry Curtis, Captain John Good to accompany him they set out from the coast of east Africa into the territory of the Masai and while staying with a Scottish missionary are attacked by a group of these tribesmen whom they overcome with heroism. There follows a voyage along an underground river to a lake in the kingdom of Zu-Vendis, a warlike white race entirely isolated ruled jointly by two sisters, Nyleptha and Sorais.
Both fall passionately in love with Curtis and this together with the rejection by Sorais of the nobleman Nasta results in a civil war between them (Sorais and Nasta's forces against those of Nyleptha, Curtis and Quatermain).
After a battle Queen Nyleptha is victorious but then threatened by the treachery of the priests who plan to murder her in the palace. Umslopogaas and one loyal warrior manage to save her from Nasta and the chief priest Agon. Umslopogaas hurled himself against Nasta as he lifted his axe against the Queen.
Umslopogaas' death is mentioned in Allan Quatermain (1887).