Placed next to the aseberia (altar tableau) on the Iyoba’s (queen mother’s) royal ancestor altar, in the palace of the ruling Oba (king), these heads (uhunmwun elao meaning 'ancestral memorial head') are commissioned by the ruling Oba after the passing of his mother. Used to commemorate his mother and to depict the position in court that she once held i.e. “her responsibility in protecting the health and well-being of her son, the Oba, thereby protecting the security and prosperity of the kingdom”.2
After the Iyoba's death, a large altar (a semi-circular mud platform onto which altar objects are placed) is created upon which the uhunmwun elao sits (along with a number of other objects and sculptures). The altar serves as a point of communication with the deceased Iyoba as well as to celebrate the life and successes of the Iyoba.
For more, see the The Tribal Eye: Kingdom of Bronze video HERE on the Oba of Benin City.