Generally known as Mrs. Macaulay, or, after her second marriage, as Mrs. Macaulay Graham, this historian and controversialist, was the second daughter of John Sawbridge of Olantigh, near Wye in Kent, who died in April 1762, by his wife, Elizabeth, daughter and heiress of George Wanley, banker in London, who died in 1733. She was born on 2nd April, and baptised at Wye on 18th April 1731. By her father's wish, she was privately educated and read much Roman history, imbibing an intense enthusiasm for 'liberty.' In June 1760, she married George Macaulay MD, a physician from Scotland, who had graduated in Padua in 1739 and settled in London in 1752. He was physician and treasurer to the Brownlow Street Lying-in Hospital and died on 16th September 1766, aged 50, leaving one daughter. The first volume of Mrs. Macaulay's' History of England,' from the accession of the Stuarts, appeared in 1763, and after her husband's death she laboured at its composition with great energy. Its publication exposed her to bitter attacks from critics who did not shrink from depreciating her personal appearance, though she was tall in stature, with a good figure.

Mrs. Macaulay was fond of gaiety and, in 1774, took a house for herself in St. James's Parade, Bath (Somerset), where she made the acquaintance of Dr. Thomas Wilson, the non-resident Rector of St. Stephen's, Walbrook, London, and was asked by him to dwell at his residence, Alfred House, No. 2 Alfred Street, Bath (Somerset), which, with his library and furniture, he placed at her full disposal. Here, she attracted many admirers, among the public proofs of whose adulation, were 'six odes,' presented to her on her birthday, 2nd April 1777, and published in the same year. She is said to have visited Paris in 1775 and to have been received with great honour. On her visit to that city in 1777, she met Franklin, Turgot, Marmontel and Madame Dubocage, and her works inspired Madame Roland with the ambition of being "la Macaulay de son pays". Dr. Johnson quizzed her and the incident at the dinner-table, when he pretended to have been converted to her principles and requested that the footman might sit down and dine with them, is well known. About 1775, she became very fond of dress, when Johnson said it was better that she should "redden her own cheeks" than "blacken other people's characters". Wilkes, who was no less furious in his hate, described her on her second return from Paris as "painted up to the eyes" and looking "as rotten as an old Catharine pear."

To the amazement of her friends she married, it is said at Leicester on 17th December 1778, William Graham, a younger brother of James Graham, the well-known quack doctor. Her second husband's age was only twenty-one and he is described as being, at that time, a 'surgeon's mate,' but upon his second marriage, on 17th May 1797, he had risen to be the Rev. William Graham MA of Misterton in Leicestershire. This second marriage of Mrs. Macaulay exposed her to much abuse and caused her the loss of many friends. Dr. Wilson acknowledged that Alfred House was hers, but threatened to hold it against her. He had placed, on 8th September 1777, within the altar-rails of St. Stephen's, Walbrook, a white marble statue of her by BF Moore, in which she was represented in the character of history, with a pen in her right hand and with her left arm leaning on some volumes of her 'History;' and had built a vault for her remains to rest in, but the statue was now taken down and the vault was sold. Among the satires published against her were 'The Female Patriot, an Epistle from C—t—e M—c—y to the Rev Dr. W—1—n on her late marriage' (1779) and 'A remarkable moving Letter (1779), which was suggested by an extraordinary epistle sent by her on her second marriage to her clerical admirer. Upon her union with Graham, she quitted Bath (Somerset) and went first to Leicestershire and then to Binfield in Berkshire. In the spring of 1784, she embarked for North America and, in June 1785, she stopped with George Washington at Mount Vernon for ten days. Three letters subsequently written to her by him appear in 'Washington's Writings'  and two more, which are deposited in the Leicester Museum, are printed in 'Notes and Queries' (1878). After her return to England, she lived in Binfield, where  she died on 22nd June 1791. A monument to her memory, with her portrait on a medallion and with the figure of an owl as the bird of wisdom, was placed in the church by her second husband.

Mrs. Macaulay possessed great talents combined with irrepressible vigour. Mary Wollstonecraft, in her 'Vindication of the Rights of Women', speaks of her as "the woman of the greatest abilities that this country has ever produced, endowed with a sound judgment, and writing with sober energy and argumentative closeness" and comments on her death "without sufficient respect being paid to her memory". Lecky distinguishes her as "the ablest writer of the new radical school". Josiah Quincy Junior, an acute-traveller from America, called on her in Bath in 1774 and, after an interview of an hour and a half, "was much pleased with her good sense and liberal turn of mind". Her most famous production was the ' History of England from the Accession of James I to that of the Brunswick line' (1763-83) which attracted great attention at the time, and brought her a considerable income, but has long dropped into oblivion. Horace Walpole confessed that  the author was prejudiced, but claimed that she "exerted manly strength with the gravity of a philosopher," and spoke of Gray's opinion as corroborating his own, that it was "the most sensible, unaffected, and best history of' England that we have had yet." From a letter written by Gray in 1766, it would appear that Pitt "made a panegyric of her 'History' in the House of Commons". Capel Lofft issued, in 1778, a printed letter of laudatory 'Observations on Mrs. Macaulay's History' and John Salt of Amwell wrote some eulogistic stanzas on it. A letter from Mirabeau, suggesting that this work should be translated into French, appears is in his 'Letters from England' and a translation into five volumes, purporting to be by Mirabeau, though it was the work of PT Guiraudet, appeared in Paris in 1791-2. De Quincey quotes an instance, not altogether conclusive, of her ignorance, and Isaac Disraeli printed a charge against her of having torn out four leaves of Harleian MS. 7379 on 12th November 1764, with the result that she had been banished from the British Museum. This accusation led to an animated correspondence in the 'Gentleman's Magazine' in 1794 and 1795 between Disraeli and her second husband, William Graham, when it was proved that no record existed of her having been forbidden to enter the museum, and that the damage to the manuscript could not be definitely attributed to her. The original manuscripts of her 'History of England' with autograph notes and corrections, are now in British Museum. She also wrote eight other works.