Bertrand Castelli was the executive producer of the original Broadway production of Hair, the self-described “American tribal love-rock musical” that helped to define a generation.

Premiered off Broadway at the New York Shakespeare Festival in 1967, the Vietnam-era hymn to flower power and hippydom transferred the following year to the Biltmore Theatre on Broadway, with the producer, Michael Butler, cited above the title and Castelli named below the title — and fondly remembered four decades later by the epoch-making musical’s guiding force.

“Everybody appreciated what Bertrand did,” recalled the show’s composer, Galt MacDermot. “He was very active and very helpful and a very nice guy and I liked him a lot.” According to MacDermot, Castelli helped with the selection of the show’s Broadway director, Tom O’Horgan, and went on to abet the promotion of a musical that in its day made history for a score celebrating such untraditional musical theatre topics as long hair, sexual liberation and drug use.

Castelli, said MacDermot, was also useful when the original production began to give rise to other productions both nationwide and internationally, including Hair’s West End premiere at the Shaftesbury Theatre and a German company whose ensemble included a very young Donna Summer.

Castelli’s own entry in the original Broadway programme for Hair cited him as a playwright and director of such works as The Umbrella, The Men’s Room and A Frenchman in New York, the last of which was turned into a film. But he was also a balletomane and bon viveur who worked on the ballets Face To Face, Green Light, Red Light and Les Algues.

That last work brought Castelli, a native Frenchman, of Corsican heritage but raised in Paris, into the heady orbit of such decisive cultural figures as Picasso and Sartre. Throughout his life Castelli was recognised not just for what he had done but for whom he knew: not long after his death, his daughter, Pandora, said that her father had worked as Picasso’s assistant and became a sometime lover of the painter’s companion, Françoise Gilot.

Hair, though, was Castelli’s ticket to the good life that he so enjoyed.

“He was a very charming guy,” said MacDermot. “People liked him; he made himself felt.” Although he spoke with a pronounced French accent, “he considered himself an amazing piece of Americana”, said MacDermot, who watched Castelli’s ready absorption into the society of which Hair made him an instant player.

The original Broadway production ran more than four years and has become a musical theatre mainstay, spawning a Milos Forman film version, starring John Savage and Treat Williams, and copious numbers of revivals on both sides of the Atlantic, including an incendiary small-scale production, directed by the American Daniel Kramer, at the Gate Theatre, London, in 2005.

A current alfresco production at the Delacorte Theatre in New York’s Central Park has been the must-have theatre ticket of the late Manhattan summer and is expected to move indoors for a commercial run at a Broadway house early next year.

Castelli was among those to acknowledge that the heady high spirits celebrated by Hair have their flip side. “It’s as though everything in Hair turned into a nightmare,” He observed of a show that remains very much part of an era before such things as Aids cut a swath through not least the musical’s original cast.

After Hair’s triumphant Broadway opening, Castelli furthered an interest in film that had begun with a supporting role in a 1959 Susan Hayward movie called Thunder In the Sun, a Western co-starring Jeff Chandler. In 1972 Castelli co-produced and co-wrote a Nixon-era satiric comedy called, aptly enough, Richard, with a cast including John Carradine, the Broadway diva Vivian Blaine and Mickey Rooney. The co-directors were Harry Hurwitz and Lorees Yerby, the latter of whom was Castelli’s wife and mother of his two daughters, though their marriage ended in divorce.

Of late he was artist in residence at the Maroma Resort and Spa in Riviera Maya, Mexico. He spent much of his time painting, swimming, and living the sort of sensualist’s life that, one cannot help but feel, remains the abiding subtext of Hair.

His death occurred during a daily swim when he was struck by a boat just offshore of the Yucatan Peninsula in Mexico.

Bertrand Castelli, producer, was born on December 3, 1939. He died on August 1, 2008, age 78