Samuel Pepys has an awful lot to answer for. For ten years, beginning in 1660, he kept a personal record of his public and private life, from his encounters with the great and the good in the Navy Office, where he worked, to his money worries, marital problems and infidelities. Very few public figures leave intimate diaries, and very few of those diaries are as candid as that of Pepys - little wonder that he used a shorthand (Shelton's system, employed for business note-taking at the time) which "made the Diary inaccessible to casual curiosity", and that he told almost nobody (including his wife) of its existence.
Pepys's prose is captivatingly vivid, his observation of his own life wonderfully unguarded. On 30 September 1665, for example, Pepys, returning home from a long day at the office, and a boozy dinner, found his wife Elizabeth "out of order", and "she took me downstairs, and there alone did tell me her falling out with both her maids, and particularly Mary". Mary, apparently, was threatening to tell Pepys that his wife was carrying on a flirtation with her painting master. Elizabeth denied any such thing; Pepys - whose jealousy regularly upset his relations with his wife - became angry. There was a row, and he threatened to go and sleep elsewhere. It was late, however, so he decided it was "best to lie in a good bed".
Mellowing, he "resolved to salve up the business rather then stir it; and so became pleasant with my wife, and to bed". This was plague season, and he reflected that they were lucky to escape the misery of sickness, thanks be to God. "So to sleep with a good deal of content."
Where else in this period do we find this kind of record of the lived detail of everyday family life? Small wonder that ever since the entire diary became readily available, in the Latham and Matthews edition of 1970 (in which Pepys's original six volumes have become a monumental 11), Pepys's intimate confessions have been borrowed, adapted, imitated and travestied, to provide the personal - and, above all, salacious - details the modern reader asks for, either in historical fiction, or in popular biography. Because of Pepys, the Restoration has been painted with monotonous regularity as the age of the bodice-ripper adventure - men in periwigs doing shady business deals and exchanging confidences in crowded coffee houses, fondling buxom seamstresses and keeping covert assignations with neighbours' wives, bedding loose women in insalubrious taverns.
Now Claire Tomalin has rescued Pepys from the posthumous reputation he made for himself. Tomalin's Pepys is a thoroughly rounded character, whose fortunes she charts with a steady hand. We watch his gradual rise, alongside his cousin and long-term employer Edward Montagu (later Earl of Sandwich and Viscount Hinchingbrooke) - a near-feudal relationship that involves Pepys's coming and going freely within the Montagu household, eating with the servants, sleeping overnight, and paying assiduous court to Lady Montagu, with whom he sustained a close, respectful friendship over the decades.
Tomalin fills out with contemporary historical detail Pepys's eyewitness accounts of what it was like to witness both the execution of King Charles I, and then, ten years later, the hanging, drawing and quartering of the regicides. Pepys's account of the Great Fire of London, which he experienced directly, and which forced him to evacuate his precious library and possessions, is given added intensity by Tomalin's deftly shaping narrative.
One of the ironies of the attention we have paid to Pepys's Diary is that, shortly after he stopped keeping it (he believed it was damaging his eyes), a dramatic downturn in his fortunes entirely altered the tenor of his life. In 1672, the man he had served all his adult life, Edward Montagu, Lord Sandwich, went down with his ship during a battle against the Dutch off the Suffolk coast. The following January, a fire broke out at the Navy Office, destroying the office and more than 20 houses, including Pepys's. All his possessions, apart from his books, were lost. At 40, the bravura, upbeat period of Pepys's life was over. How very different a diary for his final 30 years would have been.
Tomalin is frankly admiring of Pepys, not simply as a diarist, but as a writer - "Parts of [the Diary] read like a novel, parts like a farce. Its near literary relation is the fiction of Chaucer." Pepys is "both the most ordinary and the most extraordinary writer you will ever meet". His range of voices, his arresting use of direct speech, astonish her, making his animated reported exchanges a match, she feels, for any in the English language - "good enough for Ben Jonson".
Perhaps this is to overdo the literary praise. For many modern readers, I suspect, the attraction of Pepys's prose is its literary insouciance, its affected disinterest in every jot and tittle that is lovingly included in the scurrilities it recounts, its louche journalistic way of narrating events witnessed close to. We are the generation that takes it for granted that for every prominent figure's public face there is a matching, hidden, disreputable or sad underside - the Princess of Wales's Panorama interview matching the inaccessible fairy-tale princess facade; Bill Clinton, the president of the United States, revealed to be the small-time sleazebag with a penchant for thong underwear.
None the less, in Claire Tomalin, Pepys has found the biographer he deserves. Her perceptive, level-headed book finally restores to the life of the diarist its weight and dignity.
Lisa Jardine's latest book is On a Grander Scale: the outstanding career of Sir Christopher Wren (HarperCollins)