1988 concert in London a 'game-changer' for Mandela The 1988 London concert calling for the release of Nelson Mandela was a "game changer" which helped create the iconic figure the world came to know and revere, according to Lord Hughes, former leader of the British Anti-Apartheid Movement. He also says he has not forgiven Margaret Thatcher for her support of the Apartheid regime. Images and soundbites.