Bill Johnson, who has died in Johannesburg at the age of 80, was one of South Africa's finest show-jumpers, and his skills as a horse-riding instructor were much in demand by the rich set of Johannesburg's northern suburbs. He came from the wrong side of the tracks in Cape Town and set many upper-class tongues wagging when he married Mary Oppenheimer, daughter of Anglo American chairman Harry.Their much-talked-about liaison started when she began taking riding lessons from him as a teenager. It became serious after her marriage in 1965 to Oppenheimer's blue-eyed boy, Gordon Waddell, who ticked all the right boxes as far as the Oppenheimers were concerned - top private school, Cambridge, wealthy stockbroking family and British Lions rugby player.Johnson, who matriculated at Observatory Boys' High in Cape Town, never went to university, couldn't afford riding lessons, had a foul tongue and notoriously roving eye and didn't drink, ticked none of them. He did develop a penchant for cigars - "Please God may I never die with an unsmoked cigar in my case," he used to pray - but that came later.After a two-week trip together to what was then Rhodesia for a showjumping competition, they announced that they intended to marry. Both already were married, with two young children apiece. Johnson's wife, Vidian, promptly sued for divorce, as did Waddell.The Oppenheimers were horrified. Harry kept a stiff upper lip but Mary's mother, Bridget, was decidedly grumpy.Johnson didn't fit the Anglo mould at all. The fact that he had a bit of chip on his shoulder didn't help.Whereas the Oxbridge set around "HO" were excessively deferential, Johnson was almost provocatively not. When asked about his relationship with Mary, he said: "I only ride Oppenheimer horses."The Oppenheimer circle thought he was outrageously crass ("A s**t," said one). But it was precisely this "up yours" attitude that attracted Mary, a rebel at heart who wore tight-fitting leopard-print tops to fancy Anglo American dinners.In an interview with the Sunday Times after it broke the story, Johnson invited the reporter to "take a punch at my stomach to see how fit I keep myself".The wedding took place in Swaziland in December 1972. Neither of her parents attended. The marriage lasted seven years. There were no children.Johnson was born in Cape Town on September 7 1935. He and his twin, Arthur, had a modest upbringing. There wasn't enough money for riding lessons, so at the age of 20 they went to England and spent five years working at stables around the country and riding when they could.Johnson worked on a pig farm and rode the farmers' prize-winning horses - which had seen better days - in his first competition.He was eliminated in the first round, which he found unforgettably humiliating.Nothing if not bloody-minded, he spent hours going over the jumps again and again in pouring rain while the farmer drowned his sorrows in a nearby pub.Johnson learnt dressage at a ladies' finishing school in Oxfordshire. Later he won the South African dressage championship.When he moved to Johannesburg he was asked to stand in for the stable manager of the Inanda Club, who was ill. Thereafter he became the club professional for three years.With a R500 loan, six pupils and four horses, he started South Africa's first equitation centre at the Bryanston Country Club.Nine years later he had 200 horses and some of the finest stables, designed by himself, in South Africa.After he became Oppenheimer's son-in-law, he told an interviewer he worked a 12-hour day, mucked out the stables and could "handle a broom twice as well as anybody else around here".Johnson, who survived a broken neck, broken back, crushed ribs and several concussions during his showjumping career, died after two weeks on life-support, having fallen off his horse and banged his head.He is survived by a son and his fourth wife, Sandy Manasse, 40 years his junior. Like the others, she started off as a young riding pupil.1935-2016..