Kurt-Friedrich Gänzl (born 15 February 1946) is a New Zealand writer, historian and former casting director and singer best known for his books about musical theatre.

Gänzl was born Brian Roy Gallas[3] in Wellington, New Zealand, and is of Austrian descent, the son of Frederick, né Fritz Eduard Gänzl, an educator who moved to New Zealand before World War II and became Headmaster of Wellington Technical College and who adopted the name Fred Gallas, and his wife Nancy, née Agnes Ada Welsh.

[3][4] He studied law and classics at the University of Canterbury in New Zealand, receiving a master's degree in 1967 while performing as a radio and concert vocalist.

For several more years, he worked as a performer, including a 1969 season in the hit London show, The Black and White Minstrels,[5] and afterwards in Monte Carlo and on cruise ships.

At the end of the 1980s, Gänzl moved to St. Paul de Vence in the south of France with Bevan to concentrate on writing full-time.

Theatre historian John Kenrick wrote: "Only serious research libraries carry this set listing thousands of shows and individuals.

[11] After Bevan's death in 2006, Gänzl spent time as a musical critic in Berlin, Germany, and then lived in Yamba, Australia.

[1] Since 2007 he has contributed more than a thousand entries about Victorian and Edwardian singers, actors and musical theatre works, on his blog Kurt of Gerolstein.