Kibaraka
Kibaraka is a folktale sourced from the Swahili, published in late 19th century. Linguist Jan Knappert published a very similar tale with the title The Giant Horse, wherein the protagonist is also named Kibaraka. In both, a youth named Kibaraka gets entangled with a cannibal sorcerer and escapes thanks to a giant horse's help; also with the giant horse's help, he reaches another city, where he marries a princess and performs heroic feats.
The story is classified in the international Aarne-Thompson-Uther Index as ATU 314, "Goldener" (previously, "The Youth Transformed to a Horse"), in a cycle that begins with the protagonist working for the antagonist and escaping from him on a talking horse.