For six decades Barbara Stone, who has died aged 83, was a quietly dynamic force in promoting progressive cinema in her varying roles as producer, distributor, exhibitor and indefatigable facilitator.

With her husband David Stone, Barbara moved to Britain in the early 1970s after the couple’s film-making activities in Cuba had excited the attention of US intelligence. In 1974 they opened the Gate Cinema in Notting Hill, established a distribution company, Cinegate, and went on to open further London cinemas, in Brunswick Square and Camden Town, along with the smaller Mayfair Cinema.

Barbara’s debut as a director had come when she was invited by the Cuban Film Institute, along with the film-maker Adolfas Mekas and David, to shoot a 140-minute documentary, Compañeras y Compañeros (1970). This involved tours of Cuba, interviewing a cross-section of the population about the changes the revolution had brought to their lives. Many hours of out-takes are preserved in the David Stone Archive at Yale.

US-Cuban relations were at rockbottom, and their Cuban adventure and subsequent visits were not ignored by the American authorities. They prudently decamped to London with their four children.

Barbara’s career in film had begun at the avant-garde film journal Film Culture, which had been established in New York by the Mekas brothers, Jonas and Adolfas. Then in 1961, with David, who shared her passion for film, she visited Gian Carlo Menotti’s budding Spoleto arts festival in Italy. She remonstrated at the event’s neglect of film, and proposed that she should remedy the deficiency. Guided by the Mekas brothers, the Stones met, befriended, encouraged and unified young American avant-garde directors and were ready with a revelatory programme of their films for the 1962 festival.

Despite their influence on the New York avant garde, the Mekas brothers’ own efforts at film-making had been abortive. The Stones took them in hand, producing two films by Jonas, Memories of Frankenstein and The Brig (1964, shot secretly in a US marines jail), both based on stage productions by the Living Theatre, and Adolfas’s Hallelujah the Hills (1963). Later productions included Robert Kramer’s Ice (1970), Milestones (1975) and Scenes from the Class Struggle in Portugal (1977). Jerome Hill’s autobiographical Film Portrait (1973) was selected in 2003 for permanent preservation by the US National Film Registry.

After they had relocated to London, Stone still had dreams of moving into feature production, and in the 80s she developed projects with film-makers including István Szabó, Martin Scorsese and Bernardo Bertolucci. Though none of these came to fruition, she was associate producer on Freddie Francis’s The Doctor and the Devils (1985), based on a script by Dylan Thomas.

Barbara recreated herself as a vivid and popular personality at every major European film festival in her search for new talents and new films. The imaginative and financially viable programming of the Stones’ London cinemas owed much to these excursions and to her impeccable eye.

She was born in Brooklyn, New York, to Morris and Pauline Weintraub. Her father’s ambitions as a lawyer had been cut short by the Depression, and, with Pauline, Barbara and her sister, Cora, he lived over the army surplus shop which he and Pauline ran. The income from the shop was enough for regular weekend outings to double bills on 42nd Street, and for the fan magazines which became the young Barbara’s favourite reading.

She left school early to work as a model in New York’s garment district, a job that paid for night classes in English literature at Brooklyn College, part of the City University of New York. The fan magazines were discarded in favour of Film Culture, the avant-garde journal established by the Mekas brothers. Soon Barbara joined them as circulation manager and contributor. In 1957 she met David, whose varied university studies had given place to a passion for cinema comparable with hers.

In London, the kitchens of the Stones’ successive family houses became the essential Saturday-night rendezvous for international film artists passing through, alongside local critics and guests. One of Barbara’s more phenomenal feats was to produce a meal just short of cordon bleu standard for two dozen diners – who might range from Scorsese to Anouk Aimée and Bertolucci – while never missing a beat of the conversation.

In 1986, with leases expiring, the London cinemas were sold, and in the early 90s the Stones confronted the US again. Barbara was briefly managing director of the San Francisco international film festival, and served on the board of directors of the American Conservatory theatre in the city. David, having liberated himself from 60s-era addictions, took a degree in counselling, and on their return to London, ran his own drug counselling practice until his death in 2011.

Barbara had meanwhile returned to independent film production. In 2007 she produced Joanna Hogg’s debut feature, Unrelated, and in 2014, with her son, Jordan, she co-produced Roman Fever, directed by Derek Coutts from an Edith Wharton short story. At the time of her death she was developing a television series about the Roma with Coutts and her daughter, Alexandra, a producer, also collaborating with her son, Dylan, an artist, on a stage musical.

She was an energetic founding member of the board of the directors of the new Playground theatre in north Kensington, London, and was striving to develop its film activities. She had the rare good fortune to retain her model’s poise, and her active creative involvement, until the end of her life.

She is survived by her children, Alexandra, Jordan, Dylan and Ethan, and three grandchildren.

• Barbara Stone, film producer, distributor and exhibitor, born 13 December 1934; died 17 March 2018