Tarzan is born in the African jungle to human parents but raised by apes. As a boy Tarzan doesn't know he is human or that others like him exist—let alone that he is the true Lord Greystoke. Tarzan learns how to hunt, fight, and swing through the trees at the side of his adoptive mother, Kala, thinking she is his biological mother. Tarzan loves Kala more than anything; when she dies, her death causes him to pull away from his ape tribe and spend more time learning about his humanity. Thanks to the books in the Claytons' cabin, Tarzan teaches himself to read in just a few years and tries to learn all he can about what it means to be human, but he doesn't get to put it into practice until he meets the Porters and their friends. Tarzan instinctively wants to protect them, especially Jane. Her beauty captivates him, and when he is first alone with her he finds himself acting like a "primeval man" instead of the chivalrous lord he was born to be. His good sense overrules his primitive instincts, and he does everything in his power to keep Jane safe and happy. Jane's departure from Africa is the trigger Tarzan needs to seek out other humans, learn to speak the human language, and leave the jungle forever. Though Tarzan is still wild at heart, his good breeding prevents him from disrupting Jane's chances for a successful marriage with Cecil Clayton. He cares more about her happiness than his own, which is the sign of a true gentleman.
Jane Porter is a classic romantic heroine. Beautiful, feisty, and independent, she has never been in love and has little interest in marriage—until she meets Tarzan. He brings out emotions she has never felt before, and she is surprised by her desire to run away with him. She has two other suitors: Robert Canler, who only wants her for her looks and social status; and Cecil Clayton, a man she thinks of only as a friend. Jane ends up marrying Clayton because of his title and wealth, both of which will provide a comfortable life for her and her father. She still loves Tarzan, but she doesn't think he would be satisfied with a civilized life.
William Cecil Clayton, known as Cecil to his friends, is the only known heir to the Greystoke title. Wealthy in his own right, he will someday inherit his father's title, land, and money, which makes him an excellent prospect for Jane Porter. Clayton adores Jane and would do anything for her and her father, which is why he accompanies them to Africa. He is just as gallant and gentlemanly as the next titled Englishman, but Jane's interest in Tarzan brings out a most unbecoming jealous streak. His heritage and wealth prevail in the end, and he wins Jane's hand.
Lieutenant Paul D'Arnot is the French equivalent of John Clayton: brave, smart, wealthy, and genteel. He risks his life to save Jane Porter, whom he has never met, and courageously endures torture at the hands of Mbonga's tribe. After Tarzan rescues him, D'Arnot teaches Tarzan how to speak French and be a proper Western gentleman. D'Arnot even offers to share half his wealth with his new best friend. He also tells Tarzan that he is the biological son of John and Alice Clayton.
John Clayton, also known as Lord Greystoke, works for the British Colonial Office. He and his wife, Alice, are sent to Africa in 1888 so he can investigate claims of native abuse in the Belgian Congo Free State. The narrator describes Clayton in only the most flattering of terms: he is strong, brave, handsome, and smart. He single-handedly designs and constructs a sturdy log cabin at the edge of the jungle for his little family, hunts for and gathers their food, and takes care of Alice and their baby after Alice loses her mind. Despite his strength and fortitude, he is no match for Kerchak, who kills him just hours after Alice's death.
Professor Archimedes Q. Porter is an anthropology scholar; he studies human society and culture. He brings Jane Porter, Cecil Clayton, Mr. Philander, and Esmeralda to Africa under the guise of researching an ancient civilization in the Congo, but in truth he's hunting for long-lost treasure. Jane and Mr. Philander worry the professor is losing his mind, but his apparent obliviousness to his surroundings is an act to make him seem more academic and scholarly. He is completely rational when it comes to Jane's forced matrimony to Robert Canler, and he even slips into his old schoolboy vernacular when arguing with Mr. Philander. Professor Porter likes to make people think he is "above" the trivial thoughts of daily life, but his inattention to practical matters puts him in debt to Canler and puts his daughter's future on the line.