Remembering Lina Lalandi. I knew her for the final ten years of her life.

Lina Lalandi, who has died aged 91, founded the English Bach festival in 1962, and was its director from the first festival, in 1963, until her death. Its early performances of both modern and baroque music took place in Oxford before, in the 1970s, London became the focus, with guest nights at the Royal Opera House and concerts at the Banqueting House, Whitehall. Igor Stravinsky was the first president, succeeded on his death by Leonard Bernstein. Over time, the EBF moved away from modern music and concentrated on baroque opera, in period dress and with period instruments, in countless performances in the UK and abroad, at venues including the Palace of Versailles outside Paris, and the ancient Odeon of Herodes Atticus in Athens.

Lina was born in Athens, daughter of Nikolas Kaloyeropoulos, former director of the Byzantine museum and subsequently Greek minister of education, and his wife, Toula. She studied the piano at the Athens conservatoire. After the second world war, both Lina and her mother received certificates of appreciation from Field Marshal Sir Harold Alexander for "faithfully and loyally" serving the allied cause. By Lina's own account, she successfully led allied servicemen across Athens to safety, occasionally hiding them in her own bed. This must have been a memorable moment for those servicemen, as Lina was a famous beauty and became for a while a Chanel model.

After the war, Lina came to London to study, and was an early and gifted exponent of the harpsichord, as well as an eager advocate for the clavichord. She made her first solo appearance at the Royal Festival Hall in 1954 and during a successful solo career played with Ernest Ansermet and the Orchestre de la Suisse Romande.

Stravinsky, Bernstein, Iannis Xenakis, Oliver Messiaen, Karlheinz Stockhausen and other wonderful musicians were tempted to Britain by Lina, many for the first time. So many musical "firsts" were scored by the EBF that orchestras were well advised to check with her office before claiming one for themselves. Just as she had championed Bach and Couperin in her harpsichord recitals, so she proved to be an ambassador for French baroque opera, as well as operas by Gluck and Handel, through the EBF. In recognition of her work, Lina was made an OBE in 1975, an Officier de l'Ordre des Arts et des Lettres in 1979 and received, from Greece, the Gold Cross of the Phoenix and the Great Prize of Music.

Late successes for the EBF were Gluck's Telemaco in London and Athens in 2003, Rameau's Platée at the Megaron in Athens in 2006, Monteverdi's Orfeo at the Banqueting House in 2007 and, finally, Handel's Alceste in London – a work never performed in Handel's lifetime and eventually premiered by the EBF in 1989. It was repeated at the Royal Opera House in 2000 and, as her very last performance, at the Banqueting House in December 2009.

Nicholas Kenyon writes: Life in the English Bach festival office was never dull. Artists would ring: "I've just had a half-hour conversation with Lina – can you explain what it is I've agreed to do?" Working for Lina was an immersive baptism of fire for those of us starting out in the music world (it was my first-ever job, in the mid-1970s), and many of today's arts organisations are populated by Lalandi survivors who learned rapidly the challenges of mounting a supremely adventurous music festival with minimal resources. The festival was run out of houses in Belgravia that diminished in size as the festival's losses grew: Lina relied hugely on her impassively affectionate second husband, Ralph, both for support and money.

Lina was always ahead of the times: Messiaen came in the early years, and his wife Yvonne Loriod played the Catalogue d'Oiseaux to a half-empty Oxford Playhouse: but by 1973, the Messiaens returned in triumph to London, and the festival became an annual distinctive shot in the arm to London's musical life. The critics, fed by Lina's enthusiasm and cooking, loved her.

Lina's festivals were fuelled by emotional turmoil and occasional sharp practice (when she asked Paul Tortelier to play all six Bach cello suites in two concerts, she charged the audience twice, but tried to pay him one fee). They were informed by her acute artistic taste, her penetrating judgment of artists and repertory, and a visionary approach to the next thing that audiences would enjoy. Many contemporary composers have cause to be grateful for her advocacy – above all her fellow Greek Xenakis, for whose gritty and elemental music she led an enlightened crusade over the years.

But it was in Bach and baroque music that her greatest impact on current taste was felt. She was a pioneering supporter of the old-instrument generation of Philippe Herreweghe and Ton Koopman, Roger Norrington and Trevor Pinnock. She led with others the contemporary rediscovery of Rameau's operas, mounting quixotic single performances at Covent Garden on Sundays: while her strong belief in "authentic" staging did not win through, seeing the dances brought to life and hearing the intricacies of the music on period instruments was a revelation.

Lina was capable of great affection and warmth, even if there was often an ulterior motive beneath the charm. For all the chaos, working with her was immense fun; for all the complications, it was artistically wholly worth it; and for all that she was infuriatingly volatile and unpredictable, we all owe her a massively inspiring musical education. She opened our ears.

• Lina Lalandi, harpsichordist and music promoter, born 1920; died 8 June 2012