and was he associated with any theatre company?
Yes the Royal Shakespeare Company
Sebastian Shaw (actor)
Shaw was particularly known for his performances in productions of Shakespeare plays which were considered daring and ahead of their time. In 1966, he joined the Royal Shakespeare Company, where he remained for a decade and delivered some of his most acclaimed performances. He also wrote several 
who played anakin ghost in return of the jedi Sebastian Lewis Shaw where was he born? Holt, Norfolk did he go to acting school? Yes at Gresham's School and the Royal Academy of Dramatic Art. did he act on stage as well? Yes he made his acting debut at age eight at a London theatre
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Sebastian Shaw (actor) [SEP] Introduction
He described himself as a "rotten actor" as a youth and said his success was primarily due to his good looks. He claimed to mature as a performer only after returning from service in the Royal Air Force during World War II. Shaw was particularly known for his performances in productions of Shakespeare plays which were considered daring and ahead of their time. In 1966, he joined the Royal Shakespeare Company, where he remained for a decade and delivered some of his most acclaimed performances. He also wrote several poems and a novel, "The Christening", in 1975. In 1983, he appeared in the third installment of the original "Star Wars" Trilogy, "Return of the Jedi", in a brief but significant role as the redeemed Anakin Skywalker, as well as Skywalker's ghost in the original version of the film.