He was in the leadership of a communist-inspired and resourced racist and terrorist campaign. So no saint then. He eventually moved away from violence and communism and embraced peaceful political methods, but only after years of isolated imprisonment. Shame he could not have seen this sooner.
Somehow, against all the odds, he prevented South Africa from sliding into anti-white warfare or even worse.
I kind of feel he was not such a great leader himself but he was the figurehead around which more powerful leaders could mass their influence. To an extent he was their passenger.