State of the Nation, by Michael Billington

Drama critics are like sprinters: good over a short distance. But many need an overview after a life of "one-night stands", as Billington titled an earlier collection. Now, the Guardian critic for 35 years, an enthusiast and advocate, has written something much more than a round-up of published work.

State of the Nation is a history of postwar British drama, correlating theatre with our political, economic and social life. It is driven by a conviction that theatre does more than mirror "the form and pressure of the times" – it anticipates and shapes our lives. History has interplayed with our public and personal lives, from the age of Churchill, Attlee, Priestley and Coward to that of Blair, Brown, Hare and Ravenhill.

Although he deals deftly with the politics of, say, arts funding or the National Theatre, he has written a book essentially about playwrights – their landmark plays, their continuities or ruptures with their predecessors, their take on the political scene. In this, he comes up with some revisionist reinterpretations.

In his biography of Pinter, Billington brought out the connection between the "classic" early plays and the later, overtly political plays, relocating Pinter from the purely metaphysical world to the brutally physical one of torture and death-camps. In this book, he finds threads between playwrights of different eras.

He makes a telling case for Priestley as a precursor of Osborne, as an angry young man, a formal experimenter and an advocate of a publicly-funded national theatre. Indeed, Priestley's Old Labourism seems close to Billington's own credo. He admires Rattigan's understatement, but is cool to Noël Coward's "bilious antipathy to modern Britain" and immune to Ivor Novello's brittle charm.

Acknowledging the imperial power of producer "Binkie" Beaumont – "the Scargill of the iron-lilac Stage Establishment" in Osborne's words – he also sees Beaumont's shrewdness in starting a non-profit wing. It not only helped him to manipulate his taxes but gave Peter Brook, fresh out of university, a start in professional theatre. Binkie nurtured his "Brooklet" as his bright young thing.

It's customary to date the "revolution in British theatre" from 1956 and Look Back In Anger. Billington is more judicious: he notes "a perceptible shift... in which culture became a weapon of social antagonism", fuelled almost as much by the 1956 visit of Brecht's Berliner Ensemble and by Beckett's reinvention of modern drama. For Billington, though, 1950s Britain remained an oasis of "modest affluence, social stability and unquestioning acceptance of authority", whatever the impact of Osborne's rage or John Whiting's violence. Billington's historical characterisations, from "The Age of Austerity" to "New Labour, New Theatre?", are in a different league from popular television histories.

He adds his own awareness of struggles, antagonisms and counter-currents, and succinct portrayals of our leaders, as if reviewing them: Harold Wilson "combined economic nous with a popular, cheeky-chappie appeal". Indeed, the more politicians approach the relaxed authority of music-hall performers, the more he likes them.

His thread though six decades of drama is the intricate interplay between national reality and theatrical fiction. It's hard, after reading this, not to feel that dissidence is inscribed in the DNA of theatre from its origins. Dionysus, god of wine and theatre, is the disturber of the repressive rule of Pentheus, King of Thebes.

He admits a blind spot about visual theatre, dismissing pieces like The Sultan' s Elephant, last year's mammoth explosion of mythical energy into central London, as more often than not "infantile shock and sensation for jaded theatrical palettes". This will hardly endear him to a new generation of theatre-makers, whose work has enlarged the vision of playwrights and the act of theatre-going.

Compared with Tynan, he is less of a dandy. He is just as socialist as John Berger, though less publicly anguished; less costive than Perry Anderson, though with a firm historical and analytical grip. He has Richard Hoggart's common touch. Theatres don't just get the critics they deserve; sometimes they rise to the critics they get. Here, Billington has produced an account of the theatre and of Britain which, like the art he rates most highly, does not only reflect what happens, but may influence it too.

Michael Kustow's 'Peter Brook' is published by Bloomsbury

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