Sir Harold Mario Mitchell Acton CBE (5 July 1904 – 27 February 1994) was a British writer, scholar, and aesthete who was a prominent member of the Bright Young Things.

He co-founded the avant-garde magazine The Oxford Broom and mixed with many intellectual and literary figures of the age, including Evelyn Waugh, who based the character of Anthony Blanche in Brideshead Revisited partly on him.

After serving as an RAF liaison officer in the Mediterranean, he returned to Florence, restoring his childhood home, Villa La Pietra, to its earlier glory.

By 1916 submarine attacks on shipping had made the journey to England unsafe and so Harold and his brother were sent in September to Chateau de Lancy, an international school near Geneva.

It was from the balcony of his rooms in Meadow Buildings that he declaimed passages from The Waste Land through a megaphone (an episode recounted in Brideshead Revisited, through the character Anthony Blanche).

He thanked me profusely, raised the bowler with a dazzling smile, and propelled himself Deanward, an Oriental diplomat off to leave a jewelled carte de visite.

'He's the Oxford aesthete,' I informed him, 'a Victorian, his rooms in Meadow are in lemon yellow and he stands on his balcony and reads his poems through a megaphone to people passing, and he belongs to the Hypocrites' Club with Brian Howard and Robert Byron and Evelyn Waugh and all that set, they call themselves the Post-War Generation and wear Hearts on their lapels as opposed to the pre-war Rupert Brooke lot who called themselves Souls.

In the later 1920s, Harold frequented the London salon of Lady Cunard, where at various times he encountered Ezra Pound, Joseph Duveen and the Irish novelist George Moore.

A fourth collection of poems, This Chaos, was published in Paris by Acton's friend Nancy Cunard, though the Giangastone translation pointed in a more promising direction.

[15] One close observer, Alan Pryce-Jones, felt that life in Florence weighed upon Acton with its triviality, for, like his father, he was a hard worker and a careful scholar.

He translated Glue and Lacquer (1941), selected from the 17th-century writer Feng Menglong's Tales to Rouse the World, with a preface by Arthur Waley, the leading scholar-translator and member of the Bloomsbury Group.

Acton's name was first on a petition submitted to Rome in 1971 by British cultural élite, requesting that the traditional Latin rite of the Mass not be abrogated in England.

[25] In leaving his family's property and collection to New York University, Acton expressed his desire that the estate be used as a meeting place for students, faculty, and guests who might study, teach, write and do research, and as a centre for international programs.

[25] Following his death, DNA testing confirmed the existence of a half-sister born out of wedlock, whose heirs have gone to court to challenge Acton's $500 million bequest to New York University.

[26] Acton was buried beside his parents and brother in the Catholic section of the Cimitero Evangelico degli Allori in the southern suburb of Florence, Galluzzo (Italy).