According to Virginia Woolf  one of the sources on whom Kevin Jackson leans heavily for his account of what he believes to be modernism's momentous year  "in or about December, 1910, human character changed." If we look five years either side of Woolf's temporal fulcrum we find that Picasso began working on Demoiselles d'Avignon in 1906-7, Stravinsky's Le Sacre du Printemps had its public disturbance of a premiere in 1913 and J Alfred Prufrock also made his entrance. In 1914 Joyce was just beginning Ulysses, while Wyndham Lewis had published Tarr, undoubtedly one of the signature works of experimental/modernist prose. Roger Fry's hugely influential Post-Impressionist show at the Grafton Galleries in London ran over the winter of 1910-11, while the equally mould-breaking Armory Show  which included Duchamp's scandalous Nude Descending a Staircase among some 1,000 other works  followed in 1913. From 1910 on Marinetti was already tramping the European lecture circuit and shouting out "Futurism!" And during this double lustrum such figures as Bartók, Braque, Musil, Modigliani, Epstein, Kafka, Klee and Kandinsky were already hard at work.

So why 1922? In his introduction Jackson comes straight to the point: Ezra Pound declared 1922 to be year one of a new age, taking the view that the previous epoch  which he derided as the Christian one  had ended when Joyce wrote the final words of Ulysses in October of the preceding year. From the beginning of 1922 Pound took to dating his letters "p s U"  post scriptum Ulysses. The new age was thus inaugurated with the publication of Joyce's great novel, and its first year ended with the appearance of Eliot's The Waste Land. Jackson isn't insensible to the idea that modernism proper got going earlier, but he cites the twelvemonth as the period when "a skinny, shabby Irishman and a natty, quietly sinister American" set about "exploding everything that realist fiction and Georgian poetry held dear". And he imagines an "average reader of 1922, content with his beer and skittles and his Kipling", who suffers this terrifying re-evaluation of all literary values.

I'm not so sure any such average reader for either work existed: most of the 1922 critics of Ulysses Jackson quotes were either modernists themselves or reactionary members of the literary establishment intent on condemning it for obscenity. Even fellow modernists such as Woolf still attacked Joyce's novel on these grounds, and she went several snobby steps further, lambasting chapters three to six as "merely the scratching of pimples on the body of the bootboy at Claridges". (She seems to have laboured under the delusion that Joyce was irredeemably déclassé, and was presumably unaware that while his family may have been financially tail-spinning, Joyce himself was a University College Dublin classics scholar of unimpeachable erudition.)

As for Eliot's strange gallimaufry of disembodied voices and purloined tags, it hardly burst on to the world stage  there were no criers in the streets of London: "Get yer Waste Land 'ere!" But so what? Alighting on this year rather than any other allows Jackson to more handily overlay modernism as a literary movement with its proximate inspiration: modernity itself. The pre-first world war period might have provided a certain amount of technological innovation, but 1922 sees specifically the birth of mass media: the launch of the BBC, together with exponential increases in the budgeting, duration and circulation of films. By this time there was also widespread use of the telephone (although Dracula already had one in Bram Stoker's 1897 novel), and  most tellingly  in 1922 the first facsimile image was sent by telephone line.

Jackson's method is simple: to pick over a slew of accounts  from books, newspapers, diaries private and personal  then put them together into a calendar of the year. The text thus moves seamlessly from, say, the attempts of Hollywood farceur Charlie Chaplin to be taken seriously, to the low comedy of Marcel Proust challenging a rowdy to a duel in a Paris nightclub. Modernism has a reputation for being a forbidding phenomenon: its visual arts disconcertingly non-representational, its literary efforts devoid of the consolations of plot and character  even its films, it's argued, fall well short of that true desideratum: entertainment. As for critical writing about modernism, its moments of lucidity are but fulgurations illuminating the dark and incomprehensible landscape of its subject's unabashed difficulty. Constellation of Genius, by contrast, is that most counterintuitive of things, an insanely readable book about modernism. Indeed, I think it no disservice to Jackson to say that this is the primer the subject has been looking for: a way into its symbolic labyrinth for even the most literal-minded, with their Daily Mailish tastes. (This latter is TE Lawrence's coinage in a letter of August 1922 to GB Shaw  nice to think of it established so early as a synonym for Little Englander philistinism.)

It helps that the stars comprising this constellation of genius could have been comfortably fitted into the average wedding marquee  along with all their lovers (many of whom they conveniently shared). The almost cloacal closeness of the Bloomsbury set is already too well attested to, as is the comparable intimacy of the proto-surrealists under André Breton in Paris. But what Jackson's almanac demonstrates is that far from there being six degrees of separation, in the cultural world of 1922 it was only a hop and a skip from Woolf, via Katherine Mansfield, to Gurdjieff, and from there  via his daughter Svetlana  to Frank Lloyd Wright who married her mother. Or, to cite another conga line: from Eliot to his old varsity pal Scofield Thayer, editor of the literary review the Dial, we can then travel in one direction to Lady Rothermere (who although unimpeachably Daily Mailish, nonetheless financed Eliot's own review, the Criterion), or in the other to Sigmund Freud  who analysed Thayer in Vienna  and on to Freud's disciple Wilhelm Reich, who tried to persuade Albert Einstein of the efficacy of his orgone box.

I don't know whether the comparatively restricted cast list of this production is because immediately p s U it was still possible to be genuinely avant garde but what does seem worth remarking on is how curious it is to be able to read Jackson's book, while having beneath your fingertips a means of access to almost all the works he mentions. In the course of reviewing this book I watched a Chaplin two-reeler, Pay Day, and some of a notorious Swedish film, Haxan. I refreshed my ear for Louis Armstrong's trumpet style, and gazed once more on Duchamp's The Bride Stripped Bare by her Bachelors, Even. I saw Buster Keaton's last film appearance  in a 10-minute short scripted by Samuel Beckett, no less  and reminded myself of what Le Corbusier's designs for Maison Citrohan actually looked like. In 1922, if you wanted to get your hands on a copy of Ulysses you would have had to shell out the equivalent of the average manual worker's weekly wage  now it's available for a fraction of that, if not for nothing; we live in an era that may not be dated with reference to Joyce's epic of everyday life, but which nevertheless embodies in its own mass media the culturally democratising programme of this allegedly elitist novel.

 Will Self's Umbrella is published by Bloomsbury.

 This article was amended on 22 October 2012. The original described James Joyce as "a Trinity College Dublin classics scholar of unimpeachable erudition". Joyce was educated at University College, not Trinity College.