How did Monty Roberts's demonstrations before Queen Elizabeth II change his career?

Monty Roberts's demonstrations before Queen Elizabeth II in 1989 were the pivotal event that transformed his career from a respected but regionally known California horseman into an internationally recognized figure whose ideas about non-force horse training would reach a global audience. The demonstrations happened at Windsor Castle, where Roberts was invited through connections in the British horse world to show the Queen his join-up method with horses from the Royal Mews. Queen Elizabeth II, herself an accomplished horsewoman with lifelong involvement in thoroughbred racing, was reportedly deeply impressed by what she witnessed — a horse accepting join-up and then accepting a rider without any of the force that traditional British horse-breaking methods employed. The Queen's endorsement — she reportedly said that she had been involved with horses her entire life and had never seen anything like what Roberts demonstrated — provided a validation from the most credible possible source in the British equestrian world and opened doors throughout the United Kingdom and Europe that Roberts's California reputation alone would not have opened. The British audience for his subsequent demonstrations and clinics provided the foundation for the international reach that made The Man Who Listens to Horses, published seven years later, the global bestseller it became — the book was published first in the UK, where Roberts's reputation from the Windsor demonstrations had established an audience, before reaching American readers. The Queen's continued relationship with Roberts — she has invited him to give multiple demonstrations over the years and has spoken publicly about his influence on her thinking about horse training — has remained one of the defining associations of his public identity and his organization's credibility.