James Wood in The Guardian:
Henry James once said that “really, universally, human relations stop nowhere,” and that the exquisite problem of the writer is to draw the circle “within which they shall happily appear to do so”. James would never have nominated War and Peace – he famously thought it a “loose baggy monster” – but Tolstoy's novel is surely the greatest attempt in the history of the genre to represent and embody the branching infinity of human relations of which James spoke. And there is no better example of that challenge than the way in which Tolstoy's project kept growing. He wrote War and Peace between 1863 and 1868, and intended, at first, to write a domestic chronicle in the manner of Trollope (whom Tolstoy, with a few qualifications, admired). The novel would be set in 1856, and concern an aristocratic revolutionary and his return from exile in Siberia. It would be called, improbably, All's Well That Ends Well. But in order to explain the atmosphere of Russia just after the Crimean war, Tolstoy felt he had to go back to 1825, when the Decembrists, a group of largely upper-class rebels, were arrested, and either executed or exiled. And 1825, he later said, could not be described without going back to the momentous year of 1812, when Napoleon invaded Russia and occupied Moscow for a month. Yet 1812 obviously needed 1805 as a proper prelude – which is where War and Peace begins.
Inexorably, what began as Russianised Trollope widened and deepened, until it became nothing less than the attempt to write the history of Russia during the Napoleonic campaign – in fact, it became the quarry that Tolstoy had identified as a young man, in his journal: “To write the genuine history of present-day Europe: there is an aim for the whole of one's life.” And as this originally “English” novel became more complex and ambitious, so it became singular and unconventional. Tolstoy claimed that it was “not a novel”, at least in the familiar, European sense. We Russians, he said, produce strange misfits, awkward black sheep, like Gogol's unfinished picaresque, Dead Souls, and Dostoevsky's semi-fictionalised account of his time in a Siberian prison camp, The House of the Dead. Gustave Flaubert seemed to agree. Admiring and horrified, he complained that Tolstoy “repeats himself, and he philosophises”: sins good formalist novelists should not commit.
More here.