In the second instalment of historian David Olusoga’s series uncovering Britain’s forgotten black history, he looks at the British slave trade.

Visiting Bunce Island in the Sierra Leone River, Olusoga finds the ruins of a fortress which imprisoned slaves before they were shipped to British colonies.

It’s a chilling place – as one of the locals says: ‘This is one of the ugliest aspects of history, but we need to remember.’ Back in London, he learns the story of Bill Richmond, a former slave who became the first black British sports star when he took up bare-knuckle boxing in Georgian Britain.

Each story is commemorated with the unveiling of a permanent memorial, making this a deeply moving as well as a truly fascinating series.