Against enormous odds, non-violent action proved to be a major factor in the downfall of apartheid in South Africa, and the establishment of a democratic black majority government, despite predictions that the transition could come only through a violent revolutionary cataclysm. This was largely the result of conditions working against a successful armed overthrow of the system, combined with the ability of the anti-apartheid opposition to take advantage of the system’s economic dependence on a cooperative black labour force. This article traces the history of nonviolent resistance to apartheid, its initial failures, and the return in the 1980s to a largely non-violent strategy which, together with international sanctions, forced the government to negotiate a peaceful transfer to majority rule.

The Role of Non-Violent Action in the Downfall of Apartheid
Journal of Modern African Studies, Vol. 37, No. 1 (Mar., 1999), pp. 137-169

http://stephenzunes.org/articles/JournalModAfStudies1999nonviolence.pdf