27 October 1966
The United Nations (UN) debated the South West Africa issue (now Namibia) year after year with increasing acrimony. On 18 July 1966 the International Court of Justice ruled in a split vote that they had no power to decide the dispute.  That decision did not deter the Namibian lobbyists and on 27 October 1966 the UN General Assembly voted by 114 votes to two (South Africa and Portugal), with three abstentions (Britain, France and Malawi) to terminate the mandate of South Africa over South West Africa and to declare the administration of the region the responsibility of the United Nations. The UN appointed an ad hoc committee to consider practical measures for the implementation of UN administration of the territory. The SA government rejected the resolution of the General Assembly, arguing that it was unconstitutional and in conflict with international law, and declared SA's intention to continue to administrate SWA. In 1969 this UN resolution was followed by a further one, calling for the immediate withdrawal of South African administration. Since several sources confirm the month as October, it is reasonable to accept that *27 September 1966, given in one source, is not correct.
References

 Kalley, J.A.; Schoeman, E. & Andor, L.E. (eds)(1999). Southern African Political History: a chronology of key political events from independence to mid-1997, Westport: Greenwood.|

Kruger, D.W. (ed)(1979). Geskiedenis van Suid-Afrika; verwerk en bygewerk deur D.W. Kruger; 3de bygewerkte uitg., Goodwood, Cape Town: NASOU, p. 620.|

Liebenberg, B.J. & Spies, S.B. (eds)(1993). South Africa in the 20th Century, Pretoria: Van Schaik Academic, p. 440.|

Muller, C.F.J. (ed)(1981). Five Hundred years: a history of South Africa; 3rd rev. ed., Pretoria: Academica, p. 560.|

Reader's Digest. (1988). Illustrated History of South Africa: the real story, New York: Reader's Digest Association, p. 461.