27 March 1994
One month prior to the establishment of the democratic dispensation, South Africa was readmitted to the Olympic games on condition that it complied within thirty days to terms laid down by the International Olympic Committee (IOC). The terms included the abolition of Apartheid laws, the non-racial unification of sports bodies and normalisation of relations with sports bodies elsewhere in Africa. The country had been banned from the games since 1970.  
References

Keesing's Record of World Events, news Digest for March 1994, p 38087.|Morgan, B., South Africa at the Olympics, from SouthAfrica.info, [online], Available at www.southafrica.info [Accessed: 05 March 2014]