Head of a Queen Mother (Iyoba)...

Head of a Queen Mother (Iyoba) 
1750–1800 - Nigeria, Court of Benin 
Courtesy: The MET Museum of Art

In the Benin kingdom, the iyoba, or mother of the oba (king), occupies an important and historically significant place within Benin's political hierarchy.

The title was first conferred upon Idia, the mother of king Esigie, who used her political skill and supernatural abilities to save her son's kingdom from dissolution in the late fifteenth century.

Ever since that time, queen mothers have been considered powerful protectors of their sons and, by extension, the kingdom itself.

Because of the enormous esteem in which they are held, iyobas enjoy privileges second only to the oba himself, such as a separate palace, a retinue of female attendants, and the right to commission cast brass sculptures for religious or personal use...   http://tribart.blogspot.fr/2017_02_01_archive.html#1755759189924177816

The Fagalde Collection of West African Tribal Art: History of the Marka Masks of Mali, West Africa

The masks of the Marka (a Mande subgroup) originated in the landlocked country of Mali, West Africa.

Long ago masks such as the Marka were thought to be extremely powerful and had the ability to frighten away evil spirits, convey messages from the spirit world and cure illnesses.

The Marka would perform ceremonies devoted to fishing and farming, and their stylized masks would be danced to invoke the spirits to grant the community with abundant agricultural yields and a successful fishing season...

History of the Marka Masks of Mali

The Fagalde Collection of West African Tribal Art: African Rock Art - January 2017

Rock paintings and engravings are Africa’s oldest continuously practiced art form.

Depictions of elegant human figures, richly hued animals, and figures combining human and animal features - called therianthropes and associated with shamanism - continue to inspire admiration for their sophistication, energy, and direct, powerful forms...
http://tribart.blogspot.fr/2017_01_01_archive.html#7320084579284487210