Hester Thrale was Dr Johnson's “Dear Mistress” for 16 years. The period of their friendship saw the melancholic lexicographer reach his full gargantuan stature as a writer, while Hester, who did not discover her own literary voice until after his death, bloomed in the light of his admiration. For Johnson's biographer James Boswell, who remained immune to Hester's charms, she was “a little artful impudent malignant devil”. Johnson would eventually agree with him.

Hester's genius was her ability to inspire in others either great love or great hate, and what is striking in her character is how little she apparently minded, or seemed to notice, which was which. Boswell's loathing reached its peak when, in her hugely popular Anecdotes of the late Samuel Johnson (1786), Hester referred only once to a certain “Mr B-”. The revenge of Mr B was to trash Mrs T in his own Life of Johnson (1791), whose success would eventually erase her book altogether.

Born in 1741 the only child of adoring parents, Hester wrote juvenile ditties that were treated as works of incipient genius; she never doubted that she was, indeed, remarkable. That her life would also be remarkable, however, could not have been predicted. To please her rich uncle, whose estate she expected to inherit, she married in 1763 a rich brewer called Henry Thrale - or, as she put it in her diary, Thraliana, “I was sold to a man I did not like for a barrel of porter.” Mr Thrale did not speak and Mrs Thrale did not stop; she was settling down to a life of annual pregnancies (for six months of every year, as she put it, she had her head over a bowl) when a friend of her husband brought Johnson to sup at their house by the brewery in Deadman's Place in Southwark.

Had Johnson not been delighted by her, it is unlikely that Hester would have had an outlet for her intelligence and wit. Johnson liked Henry, too, and he loved a good dinner: so successful was the meeting that soon the 55-year-old widower was installed in the Thrales' country mansion in Streatham, where he slept until noon, ate peaches before breakfast and gnawed on chicken bones to his heart's content. Hester gave Johnson his first feeling of family, and he gave her a padlock in the event that he go mad and should need locking up. The Thrale children regarded him, in the memorable phrase of Johnson's biographer Walter Jackson Bate, “as a combination of friend and a sort of toy elephant”. The animal Hester resembled, Johnson remarked, was the rattlesnake.

Hester seemed happy enough as Johnson's companion, duelling her wit against his and shining in her newly acquired fame; but the truth, she later revealed, was that she found the company of this man-child a “yoke” she had to bear. “And I am never to see a face but Mr Johnson's?” she wrote in her diary. Looking on Johnson's face, she could at least avert her gaze from the face of Mr Thrale, who was eating himself to death. When he finally expired in a great gust of wind after a meal of eight courses, he left his wife, aged 40, free to cast off her other yoke as well: three years later, in 1784, Hester married Signor Piozzi, her daughters' Roman Catholic music master. Her children were appalled, her friends, including the novelist Fanny Burney, astonished, and Johnson was thrown out of paradise. His giant form bent double, his nest-like hands groping forward and his blind eyes struggling to focus, the old man dragged himself back to his London lair where he burnt all her letters, and died. “I am afraid Mrs Thrale's imprudent marriage shortened his life,” opined Mrs Montagu. Hester saw the situation differently: “Poor Johnson did not mean to use me ill, he only grew upon indulgence till patience could endure no longer.”

Was Johnson in love with Hester? He seems hardly to have known the answer himself. His feelings towards her, McIntyre suggests in his marvellously rich biography, were undoubtedly erotic, while any fondness she had for him was the result of flattery, boredom and the drag of 12 consecutive pregnancies.

Only four of her dozen children - all girls - made it to adulthood, by which point they had each disowned their mother. Distance was Hester's preferred maternal mode: of her two-year-old daughter, Susanna, she noted that she was “small, ugly & lean as ever; her Colour like that of an ill painted Wall grown dirty”. A year later, the child's colour had become “like that of a Clorotic Virgin at 15”. McIntyre, who admits to finding Hester at times baffling, suggests that such detachment must be understood in the context of the high infant-mortality rate of the 18th century. But it should also be remembered that Hester was someone who happily lived with a husband she didn't like and a house guest she found “irksome”; when she left to embark on a two-and-a-half-year honeymoon with Piozzi, she found the protests of her abandoned children an inconvenience. “In a later age,” McIntyre comments with characteristic wryness, “Hester might well have fallen foul of some of the more intrusive legislation that would find its way onto the statute book in such areas as childcare and health and safety. But then is not now.”

The problem for Hester's biographer is that Johnson's exit from her life was followed so swiftly by the happy-ever-after of her second marriage; and while she lived a further 40 years, during which time she published her letters to and from Johnson, her Anecdotes and an extraordinary dictionary of Synonyms, whose quality McIntyre is right to perceive, her life was never to be so remarkable again. There is never much to say about a happy marriage, and six weeks into her honeymoon Hester would write that, “I have experienced greater and longer felicity than I ever yet experienced.” It is hard to know, however, in what her felicity lay: she did not share her husband's love of music, and he struggled with the language she was so adept at using.

Can we forgive Hester her treatment of Johnson and her daughters? Despite McIntyre's apologies on her behalf, I am not sure that I can. In this, the best account we have of the life of Mrs Thrale-Piozzi, her supreme self-confidence seems the result of shallowness; her coldness the result of self-regard. As Mrs Thrale, she was a bearer of yokes; as Mrs Piozzi, she became, to her children at least, something of a yoke herself. Hester by Ian McIntyre

Hester by Ian McIntyre
Constable £25 pp464

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