Allan Quatermain
The narrator of the novel, Allan Quatermain is an elephant hunter and erstwhile adventurer asked to aid Sir Henry Curtis and Captain John Good in finding Sir Henry's brother Neville and the legendary mines of King Solomon. Quatermain gives his age as fifty-five at the beginning of the narrative, indicating that he has survived much longer than the average elephant hunter, who evidently expects to live about five years in the dangerous profession. Quatermain becomes the mouthpiece of the white men among the Kukuanas, and is in many ways fulfilling a priestly role when they make themselves out to be divinities. Quatermain has no qualms about playing upon the superstitious nature of the Kukuanas if it will give the men, highly outnumbered should the Kukuanas turn on them, any advantage.
Quatermain claims to be a coward, but his actions demonstrate his bravery. He is a pessimist who thinks himself a realist, but he is not afraid to undertake dangerous deeds should he deem them necessary. For all his negativity, Quatermain becomes Ignosi's most trusted advisor among the white men. It is also Quatermain who, despite his fatalism, keeps his head long enough to grab a handful of diamonds as the men seek to escape the sealed treasure chamber.
Sir Henry Curtis
Described by Quatermain as "a man of about thirty," and "one of the biggest-chested and longest-armed men I ever saw." He has grey eyes and a blond beard and hair. He enlists Quatermain's aid in rescuing his brother Neville by locating King Solomon's Mines. His desire to find his brother is so great that he offers both Quatermain and Captain Good his share of the diamonds from King Solomon's Mines if only he can locate Neville.
Sir Henry proves himself time and again to be a man of great bravery and heroism. He kills Twala's son Scragga in defense of the maiden Foulata; he does not stray far from the thick of battle when fighting for Ignosi; and he readily accepts Twala's challenge of single combat once the deposed king is captured.
Sir Henry is also compassionate. He comforts the despairing Quatermain and Good when they believe themselves doomed to die in the sealed treasure chamber. His character is also indicated by the very nature of this quest. He has no desire for the riches of King Solomon's diamond mines, so long as he can learn his brother's fate.
Captain John Good
A "short, stout, and dark" man of Sir Henry Neville's acquaintance. Quatermain rightly suspects him of being a naval man upon first seeing him. Good desires to help his friend, Sir Henry Curtis, find his brother, but he also seeks the riches of King Solomon's Mines.
Quatermain mocks Good's fastidiousness about his personal appearance. In one case, Quatermain attributes Good's near death by elephant to Good's refusal to dress appropriately for the African wild. However, Good's extreme focus on his dress gives the white men a means of convincing the Kukuanas that they are supernatural beings. Good's constantly-worn eyeglass and half-shaven face are unusual to the Kukuanas, and indicate something alien to their inexperienced eyes. On the other hand, Good's overweening pride in his appearance is dealt a blow when the Kukuanas first see him without his trousers, which necessitates a long journey without pants so that he might not cover up his "beautiful white legs."
George Neville
Brother to Sir Henry Curtis, Neville's journey to find King Solomon's diamond mines is traced by Quatermain, Sir Henry, and Captain Good in an effort to locate him. He is mostly a plot device throughout the novel, for the men find no evidence of him until they are on their way back home. By taking a different route than the one leading to Kukuanaland, the expedition finds Neville settled by an oasis, as he was injured and could neither proceed nor return. Because his quest for King Solomon's Mines is what brought them there, and because he has suffered in his search for the riches of the Mines, Captain Good and Quatermain agree to divide their share of the diamonds with Neville.
Umbopa (Ignosi)
The man first known as Umbopa to Quatermain and the others turns out to be Ignosi, son of the rightful king of the Kukuanas, who has been displaced from his throne through the machinations of Gagool and Twala. Ignosi is repeatedly described as dignified, of noble bearing, and loyal to his friends. He is a great improvement over Twala as king of the Kukuanas.
Twala
Twala, the one-eyed giant king of the Kukuanas, came by this throne through guile and murder. As the weaker twin brother, he was supposed to be killed at birth, but his softhearted mother saved his life and entrusted him to Gagool. Gagool secretly raised him to be the next king and, when the moment was right, revealed him to the people while their present king, Imefu, was ill. Twala killed Imefu on his sickbed and took the throne, driving Imefu's wife and her young son, Ignosi, from Kukuanaland to die in the wilderness.
Twala is cruel but brave. His cunning is evident in his refusal to match his spear against the white men's firearms, and in his attempts to win them to his cause before making a move against them. Unlike most of the Kukuanas, Twala is not moved by the supernatural pretensions of the white men.
Gagool
Gagooli s described as a wizened monkey-like creature. She is the wise woman of the Kukuanas, but her present function seems to be more an inciter of terror than a bringer of wisdom. She orchestrated Twala's usurpation of the throne and maintains his power through the agency of her witch-finders, who locate men who have shown some opposition to Twala and have them executed. Gagool claims to be generations old, and much of the knowledge she possesses is certainly ancient.
Foulata
Foulata is the beautiful Kukuana maiden whose misfortune it is to be selected as the first sacrifice at the dancing ceremony. She begs Captain Good for mercy, and he, along with Sir Henry and Quatermain, prevent her from being sacrificed. This intrusion into Kukuana rites sparks the civil war between Twala and Ignosi.
Foulata is tender and nurturing, and she develops a strong affection for Captain Good, even going so far as to nurse him back to health after he is wounded in battle. Quatermain dislikes her growing intimacy with Good, primarily because he sees Good as a fickle suitor who will only hurt Foulata in the end. Foulata is spared any future rejection by Good when she sacrifices her life to stop Gagool's safe escape from the treasure chamber.
Infadoos
Infadoos is the first Kukuana that the expedition encounters (with the exception of Umbopa, who is hiding his heritage). He turns out to be King Twala's half-brother and Ignosi's uncle. He is awed by the white men, and particularly by Captain Good's white legs, eyeglass, and removable teeth. He is the first and most loyal follower of the returned Ignosi, and he provides the men with valuable information which helps keep them alive and shapes their strategy against Twala. Infadoos gathers the most loyal of chiefs to see and hear Ignosi, and spreads the word that their true king has returned.
