Splendid terra cotta heads and figures found in central Nigeria date back 2,500 years , while recent excavations at Ife -LRB- the sacred city of the Yoruba people -RRB- , Igbo-Ukwu and Benin City have unearthed evidence of high-quality bronze casting from perhaps , at least at Igbo-Ukwu , as early as the ninth century A.D . The court of Benin , centered on Benin City , was the royal and administrative seat of a great kingdom powerful from the 14th to 17th centuries .