From the first Harley gave great attention to the conduct of public business, bestowing especial care upon the study of the forms and ceremonies of the House. His reputation marked him out as a fitting person to preside over the debates of the House, and from the general election of February 1701 until the dissolution of 1705 he held with general approbation the office of Speaker. For a part of this period, from 18 May 1704, he combined with the speakership the duties of the Secretary of State for the Northern Department, displacing in that office the Tory Earl of Nottingham. In 1703 Harley first made use of Defoe's talents as a political writer, and this alliance with the press proved so successful that he afterwards called the genius of Swift to his aid in many pamphlets against his opponents in politics. While he was secretary of state the union with Scotland was effected. At the time of his appointment as secretary of state Harley had given no outward sign of dissatisfaction with the Whigs, and it was mainly through Marlborough's good opinion of his abilities that he was admitted to the ministry. For some time, so long indeed as the victories of the great English general cast a glamour over the policy of his friends, Harley continued to act loyally with his colleagues. But in the summer of 1707 it became evident to Godolphin that some secret influence behind the throne was shaking the confidence of the queen in her ministers. The sovereign had resented the intrusion into the administration of the impetuous Earl of Sunderland, and had persuaded herself that the safety of the Church depended on the fortunes of the Tories. These convictions were strengthened in her mind by the new favorite Abigail Hill (a cousin of the Duchess of Marlborough through her mother, and of Harley on her fathers side), whose soft and silky ways contrasted only too favorably in the eyes of the queen with the haughty manners of her old friend, the Duchess of Marlborough. Both the Duchess and Godolphin were convinced that this change in the disposition of the queen was due to the sinister conduct of Harley and his relatives; but he was for the present permitted to remain in his office. Subsequent experience showed the necessity for his dismissal and an occurrence supplied an opportunity for carrying out their wishes. An ill-paid and poverty-stricken clerk, William Gregg, in Harley's office, was detected in furnishing the enemy with copies of many documents which should have been kept from the knowledge of all but the most trusted advisers of the court, and it was found that through the carelessness of the head of the department the contents of such papers became the common property of all in his service. The queen was thereupon informed that Godolphin and Marlborough could no longer serve in concert with him. They did not attend her next council, on 8 February 1708, and when Harley proposed to proceed with the business of the day the Duke of Somerset drew attention to their absence, when the queen found herself forced (11 February) to accept the resignations of both Harley and St John.
Harley went out of office, but his cousin, who had now become Mrs Masham, remained by the side of the queen, and contrived to convey to her mistress the views of the ejected minister. Every device which the defeated ambition of a man whose strength lay in his aptitude for intrigue could suggest for hastening the downfall of his adversaries was employed without scruple, and not employed in vain. The cost of the protracted war with France, and the danger to the national church, the chief proof of which lay in the prosecution of Sacheverell, were the weapons which he used to influence the masses of the people. Marlborough himself could not be dispensed with, but his relations were dismissed from their posts in turn. When the greatest of these, Lord Godolphin, was ejected from office, five commissioners to the treasury were appointed (August 10, 1710), and among them figured Harley as Chancellor of the Exchequer. It was the aim of the new chancellor to frame an administration from the moderate members of both parties, and to adopt with but slight changes the policy of his predecessors; but his efforts were doomed to disappointment. The Whigs refused to join in an alliance with the man whose rule began with the retirement from the treasury of the finance minister idolized by the city merchants, and the Tories, who were successful beyond their wildest hopes at the polling booths, could not understand why their leaders did not adopt a policy more favorable to the interests of their party. The clamours of the wilder spirits, the country members who met at the October Club, began to be re-echoed even by those who were attached to the person of Harley, when, through an unexpected event, his popularity was restored at a bound. A French refugee, the ex-abbé La Bourlie (better known by the name of the marquis de Guiscard), was being examined before the privy council on a charge of treachery to the nation which had befriended him, when he stabbed Harley in the breast with a penknife (March 8, 1711). To a man in good health the wounds would not have been serious, but the minister had been for some time indisposed a few days before the occurrence Swift had penned the prayer Pray God preserve his health, everything depends upon it and the joy of the nation on his recovery knew no bounds. Both Houses presented an address to the crown, suitable response came from the queen, and on Harleys reappearance in the Lower House the speaker made an oration which was spread broadcast through the country. On 23 May 1711 the minister became Baron Harley of Wigmore and Earl of Oxford and Mortimer; on the 29 May he was created Lord Treasurer, and on 25 October 1712 became a Knight of the Garter. Well might his friends exclaim that he had grown by persecutions, turnings out, and stabbings.
With the sympathy which this attempted assassination had evoked, and with the skill which the lord treasurer possessed for conciliating the calmer members of either political party, he passed through several months of office without any loss of reputation. He rearranged the nations finances, and continued to support her generals in the field with ample resources for carrying on the campaign, though his emissaries were in communication with the French king, and were settling the terms of a peace independently of England's allies. After many weeks of vacillation and intrigue, when the negotiations were frequently on the point of being interrupted, the preliminary peace was signed, and in spite of the opposition of the Whig majority in the Upper House, which was met by the creation of twelve new peers, the much-vexed Treaty of Utrecht was brought to a conclusion on 31 March 1713. While these negotiations were under discussion the friendship between Oxford and St John, who had become Secretary of State in September 1710, was fast changing into hatred. The latter had resented the rise in fortune which the stabs of Guiscard had secured for his colleague, and when he was raised to the peerage with the title of Baron St John and Viscount Bolingbroke, instead of with an earidom, his resentment knew no bounds. The royal favorite, whose husband had been called to the Upper House as Baron Masham, deserted her old friend and relation for his more vivacious rival. The Jacobites found that, although the Lord Treasurer was profuse in his expressions of good will for their cause, no steps were taken to ensure its triumph, and they no longer placed reliance in promises which were repeatedly made and repeatedly broken. Even Oxford's friends began to complain of his habitual dilatoriness, and to find some excuse for his apathy in ill-health, aggravated by excess in the pleasures of the table and by the loss of his favorite child. By slow degrees the confidence of Queen Anne was transferred from Oxford to Bolingbroke; on 27 July 1714 the former surrendered his staff as lord treasurer, and on 1 August the queen died.
On the accession of George I the defeated minister retired to Herefordshire, but a few months later his impeachment was decided upon and he was committed to the Tower on 16 July 1715. After an imprisonment of nearly two years the prison doors were opened in July 1717 and he was allowed to resume his place among the peers, but he took little part in public affairs, and died almost unnoticed in London on 21 May 1724. He married, in May 1685, Edith, daughter of Thomas Foley, of Witley Court, Worcester. She died in November 1691. His second wife was Sarah, daughter of Simon Middleton, of Edmonton. He was succeeded in his title by his son, Edward.
Text originally from the 1911 Encyclopedia Britannica.