Jaja (jä`jə), fl. 1869–87, Nigerian merchant prince. A former slave, he became an important trader in Bonny in the 1860s as a middleman between the coastal markets and the Nigerian interior. In 1869 he founded his own state at Opobo on the Gulf of Guinea. From there he controlled supplies of palm oil and opposed the efforts of British firms to penetrate the interior. The traders persuaded the British vice consul, Henry Hamilton (Sir Harry) Johnston, to act against Jaja, who was seized in 1887 and then deported to the West Indies.