Trotter was a precocious and largely self-educated young woman, who had her first novel (The Adventures of a Young Lady, later retitled Olinda’s Adventures) published anonymously in 1693, when she was but 14 years old. Her first published play, Agnes de Castro, was staged two years later, in the year 1695, at the Theatre Royal, and printed in the following year, with a dedication to the Earl of Dorset and Middlesex, from which it appears that his Lordship was one of her personal friends and advisers. This tragedy was not based upon historic fact, but upon Aphra Behn’s English translation of a French novel.

In 1696, she was famously satirised alongside Delarivier Manley and Mary Pix in the anonymous play, The Female Wits. In it, Trotter was lampooned in the figure of “Calista, a lady who pretends to the learned languages and assumes to herself the name of critic.” The following year, Trotter addressed to William Congreve a set of complimentary verses on his The Mourning Bride, and thus either created or strengthened the interest which that poet took in her literary proceedings. His published letter to her shows that they had been previously acquainted.

In 1698, her second tragedy and arguably best-liked play, Fatal Friendship, was performed at the then-new theatre in Lincoln’s-Inn-Fields. It was afterwards printed with a dedication to the Princess of Wales, and not only established Trotter’s reputation as a dramatic writer, and brought a shower of complimentary verses, but increased the number of her powerful, fashionable, and eminent friends. It may reasonably be supposed, produced great pecuniary profit.

In 1700, she was one of the presumptuous Englishwomen who, under the several names of the Nine Muses, bewailed in verse the death of John Dryden. She was consequently praised and addressed as a Muse by a troop of admiring rhymers.

Early in the year 1701, her comedy of Love at a Loss, or Most Votes carry it, was performed at the Theatre Royal, and published in the month of May of the same year, with a dedication to Lady Piers. “She had,” remarks Dr. Birch, “contracted a very early esteem for, and most intimate and unreserved friendship,” with Trotter. Later in the same year, her third tragedy, The Unhappy Penitent, was performed at Drury Lane, and published in August, with a dedication to Lord Halifax, and a set of verses, by Lady Piers, prefixed, inscribed “To the excellent Mrs. Catherine Trotter”. Also in 1701, she wrote her Defence of Mr. Locke’s Essay of Human Understanding, and it was published in May, 1702. This gained for her the personal friendship of Locke and of Lady Masham, and was, through them, the means of introducing her to many eminent persons, among them being Mr. Peter King, then a barrister and member of parliament, who was the maternal nephew of Locke.

From 1701, until her marriage in 1708, Catherine Trotter kept up a regular correspondence with her friend George Burnet, Esq., of Kemnay. During the greater part of the period he traveled in foreign lands, and more especially at the courts of Berlin and Hanover, where be spread the fame of “la nouvelle Sappho-Ecossoise,” and excited the curiosity of Leibnitz to become acquainted with her philosophical works. It may be inferred from many passages in his letters that he would gladly have raised for himself an amorous interest with this young friend; and from hers, that, with unaffected candour and cordial esteem, she repelled every approach towards a declaration of love. She had many admirers, but never was led by the persuasions of her friends, or the temptations of wealth and rank, to encourage the addresses of men for whom she felt no preference.

Considering the position and connections of her parents, it is probable that Trotter had not been trained at an early age to piety, and consequently when a crisis of the soul occurred, she probably met with a Roman Catholic teacher, and, as a natural result, she zealously adopted his creed. In this she continued for many years, resting quiescently upon its first impressions. Meanwhile, her strict observance of the fast-days proved so injurious to her health, that in October, 1703, her friend and physician, Dr. Denton Nicholas, wrote her a letter of serious remonstrance upon the subject, and desired her “to abate of those rigours of abstinence, as insupportable to a constitution naturally infirm,” requesting that his opinion might be communicated to her friends and to her confessor.

In 1704, Trotter composed a poem on the Duke of Marlborough’s gaining the battle of Blenheim, which, being highly approved of by the hero and his family, was put into print. About that period she had some hopes of obtaining, through the powerful interest of the Marlborough family, a pension from the crown, to which her father’s long services and losses in the cause of his King and country gave a plausible claim. This, however, she failed to obtain, and received only a gratuity. After the battle of Ramilies, in 1706, she produced another poem in praise of the Duke of Marlborough, and on both occasions her verses were ranked among the best which recorded his fame. In the same year, her tragedy, called The Revolution of Sweden, founded on Vertot’s account of Gustavus Ericson, was performed at the Queen’s Theatre in the Haymarket; and subsequently printed, with a dedication to Lady Harriet Godolphin, eldest daughter of the great Duke, and after his decease Duchess of Marlborough in her own right.

Rev. Cockburn confessed his love, proposed, and was accepted. He took holy orders in the Church of England in 1708, married Trotter, received the “Donative” of Nayland, near Colchester, and, leaving his bride in London to arrange her affairs and to purchase furniture, he took possession of his pastoral charge in June, and welcomed her to their new home in the autumn of the same year.

Her sister, Mrs. Inglis, residing at Salisbury, and her mother spending much of her time there, Catherine was induced to make long visits to that city, extending sometimes to the period of fifteen months. But her favourite abode was at “Mr. Finney’s, in Beaufort Buildings on the Strand,” where, in private lodgings, she could, without domestic restraint or the disturbance of young children, give herself up to literary occupations. Among the happy results of her sojournings at Salisbury was her acquaintance with Bishop Gilbert Burnet, and with his third wife, Elizabeth, eldest daughter of Sir Richard Blake, and widow of Robert Berkeley, Esq, of Spetchley. Mrs. Burnet, who had a large, independent income, took an affectionate interest in Trotter until Mrs. Burnet died in 1709.

In 1726, Rev. Cockburn convinced himself of the propriety of taking the Oath of Abjuration upon the ascension of George I, to which he had so long objected. He was appointed to St. Paul’s Chapel in Aberdeen in the following year. Thither he was accompanied by his family; and his wife bade, in that year, an everlasting farewell to London, the scene of her many triumphs and many trials.

From the year of her marriage, 1708, until 1724, Trotter had published nothing. In the latter year, she wrote her “Letter to Dr. Holdsworth”, and having sent it to him, and received an elaborate controversial answer, she published her “Letter” in January, 1727. To this, Dr. Winch Holdsworth publicly replied, and Trotter wrote an able rejoinder; but the booksellers not being willing to undertake its responsibility, the “Vindication of Mr. Locke’s Christian Principles from the injurious imputations of Dr. Holdsworth”, remained in manuscript until it was published among her collected works.

In 1732, while living at Aberdeen, she wrote the “Verses occasioned by the Busts in the Queen’s Hermitage”, which were printed in the Gentleman’s Magazine for May 1737. In August, 1743, her “Remarks upon some Writers in the Controversy concerning the Foundation of Moral Duty and Obligation” were published in a serial called “The History of the Works of the Learned”. These ‘”Remarks” were well received, and excited great admiration, and Trotter’s friend, Dr. Sharp, archdeacon of Northumberland, having read them in manuscript, engaged her in an epistolary discussion on the subject of which they treat. The correspondence began August 8, 1743, and was concluded October 2, 1747.

It is interesting to know Trotter’s opinion of the most illustrious of all her contemporaries, Bishop Butler. In letters to Mrs. Arbuthnot, written at Aberdeen, in 1738, she thus mentions him:—

In subsequent letters to her niece, Mrs. Arbuthnot, Trotter often alludes to her “good son” with all the satisfaction of a happy mother. In 1743, a daughter died; and in January, 1749, her husband did as well. Under this severe shock, her feeble health gave way. Trotter died at Longhorsley near Morpeth on 11 May 1749. She was buried beside her husband and her youngest daughter, at Longhorsley, and on their tomb was inscribed one sentence, altered from Proverbs xxxi. 31, “Let their own works praise them in the gates.”

Dr. Rutherford’s “Essay on the Nature and Obligations of Virtue” having appeared in 1744, her active mind was again aroused for public controversy, and in April 1747, her “Remarks upon the Principles and Reasonings of Dr. Rutherford’s Essay on the Nature and Obligations of Virtue, in Vindication of the contrary Principles and Beasonings enforced in the Writings of the late Dr. Samuel Clarke”, were published with a preface by Bishop Warburton. The extraordinary reputation acquired by this able work, suggested to some friends, who submitted the scheme to Lady Isabella Finch, the thought of raising a subscription for the republication of all Trotter’s works, which the author herself undertook to edit. This plan was zealously supported by Trotter’s fashionable and eminent friends, but uncontrollable circumstances prevented its full execution.