Nelson Rolihlahla Mandela was a South African anti-apartheid revolutionary and politician who served as President of South Africa from 1994 to 1999 JOHANNESBURG: South Africans united in mourning for Nelson Mandela on Friday, but some feared the anti-apartheid hero's death could leave their country vulnerable again to racial and social tensions that he did so much to pacify. As dawn broke and commuters headed to work, many expressed shock at the passing of a man who was a global symbol of reconciliation and peaceful co-existence.