The central achievement of Harley's government was the negotiation of the Treaty of Utrecht with France in 1713, which brought an end to twelve years of English and Scottish involvement in the War of the Spanish Succession.

In 1714 Harley fell from favour following the accession of the first monarch of the House of Hanover, George I, and was for a time imprisoned in the Tower of London by his political enemies.

The principles of Whiggism and Nonconformism were taught to him at an early age, and he never formally abandoned his family's religious opinions, although he departed from them in politics.

[3] During 1688 Harley acted as his father's agent in promoting support for William, Prince of Orange and the Protestant cause against the policies of James II.

[3] This recommended Robert Harley to the notice of the Boscawen family, and led to his election, in April 1689, as the parliamentary representative of Tregony, a borough under their control, whilst at the same time acting as High Sheriff of Herefordshire.

[4] From an early age, Harley paid particular attention to the conduct of public business, taking special care over the study of the forms and ceremonies of the House of Commons.

Harley supported the Toleration Bill during its passage through the Commons and he hoped for "an equal settlement of religion" to be achieved by the inclusion of Presbyterians in the Church of England.

On 14 May, Harley delivered his maiden speech in which he reminded the House of recent Tory persecutions (such as the harsh punishment of Monmouth's followers) and said that this injustice must be remedied.

Harley was pleased that both the Whigs and the Tories had agreed on placing further limits on the power of the crown and he was reported to have said that "he hoped in a little time our infamous distinctions and parties, but particularly Jacobitism, should be wholly abolished and extirpated".

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 influence 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.

The sovereign had resented the intrusion into the administration of the impetuous Lord Sunderland, and had persuaded herself that the safety of the Church of England depended on the fortunes of the Tories.

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.

In addition to citing the lax security already mentioned, Thomson writes that Harley "so arranged matters that the unhappy clerks in his office could not begin work until midnight or a little before and so were unable to leave till dawn.

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 Henry Sacheverell, were the weapons which he used to influence the masses of the people.

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.

[20] The Whigs refused to join an alliance with him, 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 favourable 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 former abbé La Bourlie (better known by the name of the Marquis de Guiscard), was being examined before the Privy Council of Great Britain on a charge of treason, when he stabbed Harley in the breast with a penknife (8 March 1711).

Fortunately for Harley, he had a taste for fine clothes, and on that occasion was wearing an ornate gold brocade waistcoat: it seems that the knife stuck in one of the ornaments.

With the sympathy which these attempted assassinations had evoked, and with the skill which the Lord Treasurer possessed for conciliating the calmer members of either political party, he passed several months in office without any loss of reputation.

He rearranged the nation's 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 House of Lords, which was met by the creation of twelve new peers nicknamed Harley's Dozen, the much-vexed Treaty of Utrecht was brought to a conclusion on 31 March 1713.

While these negotiations were under discussion, the friendship between Harley (Oxford) and St John, the latter who had become Secretary of State in September 1710, was fast changing into hatred.

The royal favourite, Abigail, whose husband had been called to the Upper House as Baron Masham, deserted her old friend and relation for his more vivacious rival.

Even Harley's (Oxford's) friends began to complain of his 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 favourite child.

On the accession of George I of Great Britain, the defeated minister retired to Herefordshire, but a few months later his impeachment[25] was decided upon and he was committed to the Tower of London on 16 July 1715.

[32] In May 1685 Harley married as his first wife Elizabeth, a daughter of Thomas Foley, and they had four children before she died in November 1691:[33] They lived at Brampton Bryan Hall, which he inherited from his father in 1700.