Pieces of broken pottery found on the island of Kilwa Kisiwani, off the coast of Tanzania. Neil MacGregor, Director of the British Museum, sifts through a selection of broken pots, found on a beach. He finds the variety of glazes and decorations reveal a string of thriving communities along the East African coast with links across the Indian Ocean and beyond. Historian Bertram Mapunda and writer Abdulrazak Gurnah help piece together the cross-cultural mix that produced the Swahili culture and language. (Duration: 15 mins)