Kurt-Friedrich Gänzl (born 15 February 1946) is a writer, musicologist, casting director and singer best known for his books about musical theatre.
After a decade-long acting and singing career and a second career as a casting director of West End shows, Gänzl has become one of the world's most important chroniclers of the history of musical theatre. According to Canal Académie, "Kurt Gänzl is an institution. No one interested in musicals and operetta can ignore that. He is the world reference – with some few others, like Gerald Bordman, Ken Bloom, or Andrew Lamb – for that subject".
Gänzl was born Brian Roy Gallas in Wellington, New Zealand and is of Austrian descent, the son of Frederick, né Fritz Eduard Gänzl, an educator, and Nancy Gallas, née Agnes Ada Welsh. He studied law and classics at University of Canterbury in New Zealand, receiving a master's degree in 1967 while performing as a radio and concert vocalist.
Early in his career, Gänzl wrote plays. His one-act plays Elektra and The Women of Troy were produced in New Zealand in 1966 and 1967 by Elmwood Players. The latter play won the British Drama League (now British Theatre Association/Drama Magazine) award in 1967. The next year, Ganzl joined the New Zealand Opera Company as a bass soloist. After the company closed, he moved to London and studied for a year at the London Opera Centre. For ten years, he worked as a performer, including a season in London's hit show, The Black and White Minstrels. His last show was Harold Fielding's Hans Andersen at the London Palladium. He then worked as a talent agent and as a casting director for over a dozen musicals and plays in London's West End theatres and for musical and operatic productions in Europe, Australia and America.
While still working as a casting director, Gänzl began writing theatre reference works. In 1986 he published his two-volume history, The British Musical Theatre (Macmillan Press, 1986), which won the Roger Machell Prize for the year's best performing-arts book and the British Library Association's McColvin Medal for the outstanding reference work (any subject) of its season. This was followed by Gänzl's Book of the Musical Theatre (1988 with Andrew Lamb), The Blackwell Guide to the Musical Theater on Record (1989), The Complete 'Aspects of Love' (1990), five editions of Musicals (1995; US: Song and Dance: The Complete Story of Stage Musicals), and The Musical: A Concise History (1997). Gänzl has published over a dozen important books on musical theatre. He has also contributed many biographical entries to the Oxford Dictionary of National Biography and Grove's Encyclopaedia of Music.