If you were asked to list the most glittering spectacles in modernist literature – Mrs Dalloway’s party, Leopold Bloom’s circadian ramble, Rupert Birkin throwing stones at a reflected moon – there is one curiosity that would not get a mention: a cardinal christening a dog recently adopted by a sentimental duchess, only to expire, a short novel later, in nocturnal pursuit of a choir boy. This scenario, along with others of just that flamboyant exoticism, is the work of Ronald Firbank, our most underrated novelist, for whom even early death by consumption could not secure immortality.

Writing through the war and into the 1920s, a disciple of Wilde and inspiration to Waugh, Firbank was ignored even more completely by his contemporaries than he has been by later critics. The little regard he enjoys is itself poisonous. His novels are acclaimed classics, but they are always minor classics. He may be labelled a maître but always a petit maître. Worse still, like the saints he often depicts, he is thought to occupy a niche. Because of their archly delicate prose, the decadent fantasia they survey and the aestheticism they are so steeped in, his works are dismissed as a minority taste, and an easily identifiable one – effete, homosexual. In a word, camp.

Yet Firbank is as bold, as brilliant, and as artistically substantial, as any of his contemporaries, and great literature is not addressed to cults or cliques. As Brigid Brophy, his most passionate resurrectrix and another forgotten novelist, points out, it was Firbank who applied the aestheticism about which Wilde had theorised, but which he could never convert successfully into art. It was Firbank, moreover, who first, from 1915, escaped from the wreckage of Victorian narrative. His novels are candle-lit processions of images, each held reverentially aloft like a gilded icon, accompanied not by chanting but by the most extraordinary dialogue. Snatches of overheard conversation, gobbets of wit, are pieced together with those vivid fragments of description to create a sensibility, supported by none of the scaffolding that frames conventional novels.

Why then the sense of puniness? I suspect that, not uncommonly, Firbank has been done in not by his detractors but by his greatest fans. For some, the minority to whom he is alleged to cater, Firbank’s flourishes are enchanting in themselves, are so bewitching in fact, and so rare, that they come to overshadow the technical genius and aesthetic power that sustain them. We take such delight in jewelled pyjamas and drunken hallucinations about St Theresa that we forget, or at least forget to mention, the art these fancies serve. We admire Firbank, I fear, as Janeites in Regency costume admire Austen: for reasons ultimately superficial, and in doing so we put everyone else off. To be rated more highly, then, Firbank should perhaps be rated better.