The territory of present-day Abia State was home to several important Igbo groups, most notably the people of Arochukwu, who formed the powerful Aro Confederacy from the 17th to early 20th century. The Aro, through the oracle at Ibini Ukpabi (Long Juju), controlled extensive trade networks and religious influence across much of southeastern Nigeria and beyond.
Other major groups include the Ngwa, Ohafia (famous for their warrior traditions and age-grade system), Ibeku, Ubakala, and the peoples of Bende and Isuikwuato. These communities maintained sophisticated systems of governance through age grades, title societies and councils of elders.