This week Neil MacGregor's history of the world is exploring the impact of the great European age of expansion and discovery during the 15th and 16th Centuries. In the last programme he described the technology that allowed Europeans to sail around the world in great galleons, the "space ships of their age". Today he looks at what happens when Europeans started trading in West Africa and first came upon the ancient culture of Benin in present day Nigeria. Neil describes the world of this hugely successful warrior kingdom and the culture that produced such exquisite artwork. He also describes what happened when the British raided Benin at the end of the 19th Century and the effect that these brass portraits first had when they arrived in London. The artist Sokari Douglas Camp reflects on the sculptures as art while the Nigerian poet and playwright Wole Soyinka reacts to the violent history of Benin and the loss of part of their great heritage. Producer: Anthony Denselow