Six foot four, and twenty-one stone; wearing a cape and carrying a swordstick, or a loaded revolver: G. K. Chesterton was a hard man to ignore. And not only in person; in print, he was if anything more daunting and improbable. He bestrode a dozen genres. Novelist, essayist, biographer, poet, playwright, historian, journalist, Christian apologist, literary and social critic: he produced thousands of essays, hundreds of poems and short stories, around eighty books and several plays. Whatever his contemporaries thought of him, his provoking and prolific energies disallowed indifference. It was not possible not to have an opinion on the man Bernard Shaw called a ‘colossal genius’. He was simply too massive.

At his Requiem Mass in Westminster Cathedral on 27 June 1936, Monsignor Ronald Knox declared: ‘The man whom we laid to rest the other day in the cemetery at Beaconsfield was one of the greatest men of his time.’ Panegyrists are expected to be affectionately extravagant. Knox, though, expressed more than rheumy-eyed nostalgia for a great man departed; his is a clearsighted vision of a future without that great man. ‘If posterity neglects him,’ Knox continued, ‘it will pronounce judgement not upon him, but upon itself.’ These are hard words to read. Knox's proleptic judgement on posterity is a finger pointed at us. For Chesterton has indeed been neglected. Although there are signs that his star may again be in the ascendant, no other figure so loved and influential in the twentieth century is now so little read or discussed in the twenty-first.

Why has he ceased to seem relevant? The question is a perplexing one. Knox emphasized Chesterton's importance ‘as a prophet in an age of false prophets’, and subsequent biographers have vied in their accounts of how time has told in his favour: from his presages over the Second World War and the rise and fall of Communist Russia, to his foreboding of eugenics and psychiatry (and indeed about man's relationship to science in general).