Onitsha Mmili was known as Ado N'Idu by migrants who departed from the vicinity of the Kingdom of Benin near the far western portion of Igboland (near what is now Agbor), after a violent dispute with the Oba of Benin that can be tentatively dated to the early 1500s [REF].
After their arrival on the east bank (Onicha-mmili, "Onitsha-on-water", see above), the community gradually became a unitary kingdom, evolving from a loosely organized group of "royal" villages to encompass "non-royal" villages comprising Igala settlers, and the native Igbos to form a more centralized entity [REF].