In his introduction to the first volume of his defining biography of John Ruskin, Tim Hilton, who has died aged 82, wrote: “When I was an undergraduate in the early 1960s I was asked to understand that an interest in Ruskin was as foolish as an enthusiasm for modern art.” It is confirmation of Tim’s resistance to convention that his life became defined by both subjects.

Tim led the spectacular revival of interest in Ruskin since the 60s and his biography is unmatched. He began work on this masterpiece in the early 70s. John Ruskin: The Early Years appeared in 1985, but it was not until 2000 that John Ruskin: The Later Years followed.

Tim’s starting point was that the 39 volumes of the library edition of Ruskin’s works were “incomplete and often intentionally misleading”, and this meant starting again. He went through considerable privations to achieve this. There was a good spell as Alistair Horne fellow at St Antony’s College, Oxford (1976-77), but also cold winters in holiday accommodation in Bembridge, Isle of Wight, where the most important Ruskin archive was then kept.

Tim’s contrariness stemmed from his childhood as the only son of Margaret (nee Palmer) and Rodney Hilton, communists who had met at Oxford in the 30s and became academics at the University of Birmingham, the city where Tim was born.

Rodney was a founder member of the Communist Party Historians Group, which contributed to the split in the British Communist party following Stalin’s death in 1953. He and Margaret left the party in 1956, but until then had been organisers of weekly meetings that their son – known as Timoshenko after a Red Army marshal rather than by his given name, John – was obliged to attend.

It gave Tim a horror of formal meetings that persisted throughout his life. His escape was serious cycling, for which he had talent, and it was an elderly member of the free-wheeling Clarion cycling club who first told him about Ruskin.

It was not a happy childhood. His parents divorced in 1951, and Tim was taken into care by Birmingham council. He was sent to school at Tettenhall college in Wolverhampton, then to Aston Technical College (now Birmingham City University), both of which he disliked, but he developed an intense habit of reading. For a period he worked in a Typhoo Tea factory, and hoped to go to art school, but he went to his father’s Oxford college, Balliol, where he studied English (1961-64).

He had inherited his father’s taste for good drink and good food, learning French with communist family friends in Paris, and he did little academic work, though he fed his mind. Towards the end of his time at Oxford he formed a close relationship (they had the honeymoon, but not the marriage) with the future journalist Nuala O’Faolain, who wrote of him: “From the moment I met him I enrolled in his one-person university. He conducted it in pubs, walking the streets, in wonderful letters packed and bursting with knowledge and ideas. He knew about the history of art and about paintings, which were his great passion. But he also knew about model villages, how to play bar billiards, classic French cooking, the early history of Aston Villa, Soviet songs, the history of witchcraft. He was loud and happy and shabby and vivid, and – impersonal.”

From Oxford, Tim went on to the then small Courtauld Institute in London to begin a PhD. The director, Anthony Blunt, set him and a fellow postgraduate, Anita Brookner, to teach a course on art criticism, Tim teaching the English tradition, Brookner the French. After two years he became a freelance critic, and taught in art schools, principally Birmingham, Norwich and St Martin’s in London. He loved the talk in art schools and was an inspiring teacher, because he believed artists learned by doing.

The 60s and 70s were what he called “the anarchic golden age of British art schools”, and he enjoyed them to the full. He became close friends with many artists, including Gillian Ayres, Terry Atkinson, Michael Bennett, Anthony Caro, Barrie Cook, Barry Flanagan, John McLean, Ronnie Rees and John Walker. He wrote introductory essays for artist catalogues and worked on shows for the British Council. He claimed to have a photographic memory for paintings. His critical mentor was the American Clement Greenberg, “Uncle Clem”, with whom he drank vodka in New York and London, and whose Art and Culture (1961) he thought “the best single work of modern art criticism”.

His own taste embraced early Picasso, abstract expressionism and its successors, and the abstract sculpture coming from Caro and the St Martin’s sculpture department. He despised video and had little time for the Young British Artists. He could be terrifyingly rude and frightening to PRs, and thought the Turner prize “a charade”.

Tim embraced the hard-drinking bohemian world of a decaying Fitzrovia: the Museum Tavern (unofficial office of Studio International), the Plough, the Coach and Horses, the French, Bradley’s Spanish Bar, and many others besides. But he also worked long hours in the library of the British Museum. He was not proud of his first-written book, Keats and His World (1971), but the first-published, The Pre-Raphaelites (1970), became very popular. His critical study Picasso appeared in 1976, The Sculpture of Phillip King in 1992.

In 1984 he married Alexandra Pringle, then working at Virago, and moved from a cottage outside Oxford to Hampstead, north London, where a large garden house was built for him and his books. He continued as a journalist, writing first for the Guardian and then the Independent on Sunday, and did the housekeeping – he was a great cook.

A son, Daniel, was born in 1986, and Tim became a devoted father. But his mood and drinking became increasingly problematic. He explained the time he had been able to afford on Ruskin by saying: “There are such things as journalism and wives.” In 1999 Pringle left him and they divorced in 2000.

Following this collapse Tim was rescued by a former acquaintance from the Courtauld, the architectural historian Lynda Fairbairn. They left London and moved to the cottage near Beccles in Suffolk that he had acquired to continue his passion for cycling. They married in 2005.

The year before, he published the delightfully eccentric One More Kilometre and We’re in the Showers: Memoirs of a Cyclist. The memoirs are interleaved with a history of European cycling that celebrates “the freedom to go where one wills” and the ruling value of “happiness”, an idea understood in terms of his communist childhood. He also wrote a full-length study of Van Gogh, but a dispute with the publisher over illustrations led to its non-appearance.

With 20 different cycles in his shed, Hilton continued to ride until February last year, by which time he had had a heart bypass and a minor stroke, and broken his hip. He continued to work on Ruskin studies. To the end he remained what he had always been, a wayward and brilliant critic and scholar, an elegant writer, and one of the last true bohemians, completely unconventional, certain of his views, and who lived his whole life as he pleased.

He is survived by Lynda and Daniel.

• Tim (John Rodney) Hilton, art critic, born 7 July 1941; died 6 January 2024