Disclaimer: this information is what I understood at the time. New research, different spellings and better information are certainly available.
Years ago, when I was teaching art to small children in Paterson, I realized that my art education at Montclair State had included very little information on African art. Since my students were mostly African American, I figured I better learn more, and quickly. The bronze bas relief sculptures, the stylized wooden animals, and the ancient masks were all great hits. The kids loved making Romeare Bearden colleges. One of the things that really sang to me was the Nkisi Nkondi: wooden figures with all sorts of nails and shards hammered into them: