Abia, state, east-central Nigeria. Abia was administratively created in 1991 from the eastern half of former Imo state. It is bordered by the states of Enugu and Ebonyi to the north, Akwa Ibom to the east and southeast, Rivers to the south and southwest, and Imo and Anambra to the west. Abia includes areas of oil-palm bush and tropical rain forest in its southern part and woodland savanna in its hilly north. Most of the population is engaged in agriculture; yams, taro, corn (maize), rice, and cassava are the staple crops, and oil palm is the main cash crop. Mineral resources include lead and zinc.