His profile rose as he became an envoy to the U.S. and United Nations, then assumed the post of foreign minister in 1977, serving mainly under PW Botha, to whom he was not related and who died in 2006.
"As you know, originally we were enemies", Mr Botha told the BBC in 2013.
"Of course all that had to change. He played the role of a saviour".
Regarded as a skilled behind-the-scenes negotiator who loosened adversaries up over rounds of drinks, Botha's accomplishments included securing a peace protocol that ended South Africa's military involvement in Angola, where Cuban troops had been sent to defend the Marxist government.
But he also served as a minister in Nelson Mandela's first post-apartheid government, praising Mr Mandela as a healing figure.
"It was thus right that he should receive a position in President Mandela's Cabinet, where he served as Minister of Minerals and Energy".
Botha had the unenviable job of defending apartheid on the world stage as South Africa grew increasingly isolated, facing economic sanctions overseas while imposing a state of emergency at home and attempting to destabilize its African neighbors.
"His wife Ina was with him until the end", he said.
Roelof Frederik Botha was born in 1932 in Rustenburg, Transvaal.
His profile rose as he became an envoy to the U.S. and United Nations, then assumed the post of foreign minister in 1977, serving mainly under PW Botha.
Stalwart politician Pik Botha will be remembered as a good person, in a bad system, according to head of the Inkatha Freedom Party Mangosuthu Buthelezi.