10 May 1994
After South Africa's first national democratic elections held in April 1994, the president of the African National Congress (ANC), Nelson Mandela, was sworn in as South Africa's first black president at the Union Buildings, Pretoria after being unanimously elected by parliament. He replaced the outgoing National Party leader F.W. de Klerk. Click here to read Mandela inaugural speech.  
References

Ndabam D., (1994), 'The world at Mandela's feet', from the Sowetan, 10 May, [online], Available at www.southafrica.info [Accessed: 10 July 2013]|

(2005). 'Pretoria 1855-2005: Chronologie 1798-1935'.