Robert Arthur Talbot Gascoyne-Cecil, 3rd Marquess of Salisbury, KG, GCVO, PC (3 February 1830 – 22 August 1903), known as Lord Robert Cecil before 1865 and as Viscount Cranborne from 1865 until 1868, was a British Conservative statesman and thrice Prime Minister, serving for a total of over 13 years. He was the first British Prime Minister of the 20th century and the last Prime Minister to head his full administration from the House of Lords.

Lord Robert Cecil was first elected to the House of Commons in 1854 and served as Secretary of State for India in Lord Derby's Conservative government from 1866 until his resignation in 1867 over its introduction of Benjamin Disraeli's Reform Bill that extended the suffrage to working-class men. In 1868 upon the death of his father, Cecil was elevated to the House of Lords. In 1874 when Disraeli formed an administration Salisbury returned as Secretary of State for India and in 1878 was appointed Foreign Secretary and played a leading part in the Congress of Berlin, despite doubts over Disraeli's pro-Ottoman policy. After the Conservatives lost the1880 election and Disraeli's death the year after, Salisbury emerged as Conservative leader in the House of Lords, with Sir Stafford Northcote leading the party in the Commons. He became Prime Minister in June 1885 when the Liberal leader William Ewart Gladstone resigned, and he held the office until January 1886. When Gladstone came out in favour of Home Rule for Ireland, Salisbury opposed him and formed an alliance with the breakaway Liberal Unionists and he won the subsequent general election. He remained Prime Minister until Gladstone's Liberals formed a government with the support of the Irish Nationalist Party, despite the Unionists gaining the largest number of votes and seats in the 1892 general election. However the Liberals lost the 1895 general election and Salisbury once again became Prime Minister, leading the Unionists to war against the Boers and another electoral victory in 1900 before relinquishing the premiership to his nephew Arthur Balfour. He died a year after in 1903.

Lord Robert Cecil was the second son of the 2nd Marquess of Salisbury. In 1840 he went to Eton College, where he did well in French, German, the classics and theology. However he left in 1845 due to intense bullying. In December 1847 he went to Christ Church, Oxford although he received an honorary fourth class in mathematics conferred by nobleman's privilege due to ill health. Whilst at Oxford he associated himself with the Tractarian movement.

In April 1850 he joined Lincoln's Inn but subsequently did not enjoy law. His doctor advised him to travel for his health and so in July 1851 to May 1853 Cecil travelled through Cape Colony, Australia, Tasmania and New Zealand. He disliked the Boers and wrote that free institutions and self-government could not be granted to the Cape Colony because the Boers outnumbered the British three-to-one and "it will simply be delivering us over bound hand and foot into the power of the Dutch, who hate us as much as a conquered people can hate their conquerors". He found the Kaffirs "a fine set of men – whose language bears traces of a very high former civilisation", similar to Italian. They were "an intellectual race, with great firmness and fixedness of will" but "horribly immoral" as they lacked theism. In the Bendigo goldmine of Australia he claimed that "there is not half as much crime or insubordination as there would be in an English town of the same wealth and population". 10,000 miners were policed by four men armed with carbines and at Mount Alexander 30,000 people were protected by 200 policemen, with over 30,000 ounces of gold mined per week. He believed that there was "generally far more civility than I should be likely to find in the good town of Hatfield" and claimed this was due to "the government was that of the Queen, not of the mob; from above, not from below. Holding from a supposed right (whether real or not, no matter) and from “the People the source of all legitimate power”." Cecil said of the Maori of New Zealand: "The natives seem when they have converted to make much better Christians than the white man". A Maori chief offered Cecil five acres near Auckland, which he declined.

He entered the House of Commons as a Conservative in 1853, as MP for Stamford in Lincolnshire. He retained this seat until entering the peerage and it was not contested during his time as its representative. In his election address he opposed secular education and "ultramontane" interference with the Church of England which was "at variance with the fundamental principles of our constitution". He would oppose "any such tampering with our representative system as shall disturb the reciprocal powers on which the stability of our constitution rests". In 1867, after his brother Eustace complained of being addressed by constituents in a hotel, Cecil responded: "A hotel infested by influential constituents is worse than one infested by bugs. It's a pity you can't carry around a powder insecticide to get rid of vermin of that kind".

In December 1856 Cecil began publishing articles for the Saturday Review, which he contributed anonymously for the next nine years. From 1861 to 1864 he published 422 articles in it, in total the weekly published 608 of his articles. The Quarterly Review was the foremost intellectual journal of the age and of the twenty-six issues published between spring 1860 and summer 1866, Cecil had anonymous articles in all but three of them. He also wrote lead articles for the Tory daily newspaper the Standard. In 1859 Cecil was a founding co-editor of Bentley's Quarterly Review, with J.D. Cook and Rev. William Scott, but this closed after four issues.

Salisbury criticised the foreign policy of Lord John Russell, claiming he was "always being willing to sacrifice anything for peace ... colleagues, principles, pledges ... a portentous mixture of bounce and baseness ... dauntless to the weak, timid and cringing to the strong". The lessons to be learnt from Russell's foreign policy, Salisbury believed, were that he should not listen to the Opposition of the press otherwise "we are to be governed ... by a set of weathercocks, delicately poised, warranted to indicate with unnerving accuracy every variation in public feeling". Secondly: "No one dreams of conducting national affairs with the principles which are prescribed to individuals. The meek and poor-spirited among nations are not to be blessed, and the common sense of Christendom has always prescribed for national policy principles diametrically opposed to those that are laid down in the Sermon on the Mount". Thirdly: "The assemblies that meet in Westminster have no jurisdiction over the affairs of other nations. Neither they nor the Executive, except in plain defiance of international law, can interfere [in the internal affairs of other countries] ... It is not a dignified position for a Great Power to occupy, to be pointed out as the busybody of Christendom". Finally, Britain should not threaten other countries unless prepared to back this up by force: "A willingness to fight is the point d'appui of diplomacy, just as much as a readiness to go to court is the starting point of a lawyer's letter. It is merely courting dishonour, and inviting humiliation for the men of peace to use the habitual language of the men of war".

In 1866 Lord Robert, now Viscount Cranborne after the death of his older brother, Cranborne entered the third government of Lord Derby as Secretary of State for India. When in 1867 John Stuart Mill proposed a type of proportional representation, Cranborne argued that: "It was not of our atmosphere — it was not in accordance with our habits; it did not belong to us. They all knew that it could not pass. Whether that was creditable to the House or not was a question into which he would not inquire; but every Member of the House the moment he saw the scheme upon the Paper saw that it belonged to the class of impracticable things".

On 2 August when the Commons debated the Orissa famine in India, Cranborne spoke out against experts, political economy, and the government of Bengal. Utilising the Blue Books, Cranborne criticised officials for "walking in a dream ... in superb unconsciousness, believing that what had been must be, and that as long as they did nothing absolutely wrong, and they did not displease their immediate superiors, they had fulfilled all the duties of their station". These officials worshipped political economy "as a sort of “fetish” ... [they] seemed to have forgotten utterly that human life was short, and that man did not subsist without food beyond a few days". Three quarters of a million people had died because officials had chosen "to run the risk of losing the lives than to run the risk of wasting the money". Cranborne's speech was received with "an enthusiastic, hearty cheer from both sides of the House" and Mill crossed the floor of the Commons to congratulate him on it. The famine left Cranborne with a lifelong suspicion of experts and in the photograph albums at his home covering the years 1866-67 there are two images of skeletal Indian children amongst the family pictures.

When parliamentary reform came to prominence again in the mid-1860s, Cranborne worked hard to master electoral statistics until he became an expert. When the Liberal Reform Bill was being debated in 1866, Cranborne studied the census returns to see how each clause in the Bill would affect the electoral prospects in each seat. Cranborne did not expect Disraeli's conversion to reform, however. When the Cabinet met on 16 February 1867, Disraeli voiced his support for some extension of the suffrage, providing statistics amassed by Robert Dudley Baxter, showing that 330,000 people would be given the vote and all except 60,000 would be granted extra votes. Cranborne studied Baxter's statistics and on 21 February he met Lord Carnarvon, who wrote in his diary: "He is firmly convinced now that Disraeli has played us false, that he is attempting to hustle us into his measure, that Lord Derby is in his hands and that the present form which the question has now assumed has been long planned by him". They agreed to "a sort of offensive and defensive alliance on this question in the Cabinet" to "prevent the Cabinet adopting any very fatal course". Disraeli had "separate and confidential conversations ... carried on with each member of the Cabinet from whom he anticipated opposition [which] had divided them and lulled their suspicions". That same night Cranborne spent three hours studying Baxter's statistics and wrote to Carnarvon the day after that although Baxter was right overall in claiming that 30% of £10 rate payers who qualified for the vote would not register, it would be untrue in relation to the smaller boroughs where the register is kept up to date. Cranborne also wrote to Derby arguing that he should adopt 10 shillings rather than Disraeli's 20 shillings for the qualification of the payers of direct taxation: "Now above 10 shillings you won't get in the large mass of the £20 householders. At 20 shillings I fear you won't get more than 150,000 double voters, instead of the 270,000 on which we counted. And I fear this will tell horribly on the small and middle-sized boroughs".

On 23 February Cranborne protested in Cabinet and the next day analysed Baxter's figures using census returns and other statistics to determine how Disraeli's planned extension of the franchise would affect subsequent elections. Cranborne found that Baxter had not taken into account the different types of boroughs in the totals of new voters. In small boroughs under 20,000 the "fancy franchises" for direct taxpayers and dual voters would be less than the new working-class voters in each seat. The same day he met Carnarvon and they both studied the figures, coming to the same result each time: "A complete revolution would be effected in the boroughs" due to the new majority of the working-class electorate. Cranborne wanted to send his resignation to Derby along with the statistics but Cranborne agreed to Carnarvon's suggestion that as a Cabinet member he had a right to call a Cabinet meeting. It was planned for the next day, 25 February. Cranborne wrote to Derby that he had discovered that Disraeli's plan would "throw the small boroughs almost, and many of them entirely, into the hands of the voter whose qualification is less than £10. I do not think that such a proceeding is for the interest of the country. I am sure that it is not in accordance with the hopes which those of us who took an active part in resisting Mr Gladstone's Bill last year in those whom we induced to vote for us". The Conservative boroughs with populations less than 25,000 (a majority of the boroughs in Parliament) would be very much worse off under Disraeli's scheme than the Liberal Reform Bill of the previous year: "But if I assented to this scheme, now that I know what its effect will be, I could not look in the face those whom last year I urged to resist Mr Gladstone. I am convinced that it will, if passed, be the ruin of the Conservative party".

When Cranborne entered the Cabinet meeting on 25 February "with reams of paper in his hands" he begun by reading statistics but was interrupted to be told of the proposal by Lord Stanley that they should agree to a £6 borough rating franchise instead of the full household suffrage, and a £20 county franchise rather than £50. The Cabinet agreed to Stanley's proposal. The meeting was so contentious that a minister who was late initially thought they were debating the suspension of habeas corpus. The next day another Cabinet meeting took place, with Cranborne saying little and the Cabinet adopting Disraeli's proposal to bring in a Bill in a week's time. On 28 February a meeting of the Carlton Club took place, with a majority of the 150 Conservative MPs present supporting Derby and Disraeli. At the Cabinet meeting on 2 March, Cranborne, Carnarvon and General Peel were pleaded with for two hours to not resign but when Cranborne "announced his intention of resigning ... Peel and Carnarvon, with evident reluctance, followed his example". John Manners observed that Cranborne "remained unmoveable". Derby closed his red box with a sigh and stood up, saying "The Party is ruined!" Cranborne got up at the same time, with Peel remarking: "Lord Cranborne, do you hear what Lord Derby says?" Cranborne ignored this and the three resigning ministers left the room. Cranborne's resignation speech was met with loud cheers and Carnarvon observed that it was "moderate and in good taste – a sufficient justification for us who seceded and yet no disclosure of the frequent changes in policy in the Cabinet".

Disraeli introduced his Bill on 18 March and it would extend the suffrage to all rate-paying householders of two years' residence, dual voting for graduates or those of a learned profession, or those with £50 in governments funds or in the Bank of England or a savings bank. These "fancy franchises", as Cranborne had foreseen, did not survive the Bill's course through Parliament; dual voting was dropped in March, the compound householder vote in April; and the residential qualification was reduced in May. In the end the county franchise was granted to householders rated at £12 annually. On 15 July the third reading of the Bill took place and Cranborne spoke first, in a speech which his biographer Andrew Roberts has called "possibly the greatest oration of a career full of powerful parliamentary speeches". Cranborne observed how the Bill "bristled with precautions, guarantees and securities" had been stripped of these. He attacked Disraeli by pointing out how he had campaigned against the Liberal Bill in 1866 yet the next year introduced a Bill more extensive than the one rejected.

In his article for the October Quarterly Review, entitled ‘The Conservative Surrender’, Cranborne criticised Derby because he had "obtained the votes which placed him in office on the faith of opinions which, to keep office, he immediately repudiated ... He made up his mind to desert these opinions at the very moment he was being raised to power as their champion". Also, the annals of modern parliamentary history could find no parallel for Disraeli's betrayal; historians would have to look "to the days when Sunderland directed the Council, and accepted the favours of James when he was negotiating the invasion of William". Disraeli responded in a speech that Cranborne was "a very clever man who has made a very great mistake".

In 1868, on the death of his father, he inherited the Marquessate of Salisbury, thereby becoming a member of the House of Lords. From 1868 and 1871, he was chairman of the Great Eastern Railway, which was then experiencing losses. During his tenure, the company was taken out of chancery, and paid out a small dividend on its ordinary shares.

He returned to government in 1874, serving once again as India Secretary in the government of Benjamin Disraeli, and Britain's Ambassador Plenipotentiary at the 1876 Constantinople Conference. Salisbury gradually developed a good relationship with Disraeli, whom he had previously disliked and mistrusted. In 1878, Salisbury succeeded Lord Derby (son of the former Prime Minister) as Foreign Secretary in time to help lead Britain to "peace with honour" at the Congress of Berlin. For this he was rewarded with the Order of the Garter. Following Disraeli's death in 1881, the Conservatives entered a period of turmoil. Salisbury became the leader of the Conservative members of the House of Lords, though the overall leadership of the party was not formally allocated. So he struggled with the Commons leader Sir Stafford Northcote, a struggle in which Salisbury eventually emerged as the leading figure.

In 1884 Gladstone introduced a Reform Bill which would extend the suffrage to two million rural workers. Salisbury and Northcote agreed that any Reform Bill would be supported only if a parallel redistributionary measure was introduced as well. In a speech in the Lords, Salisbury claimed: "Now that the people have in no real sense been consulted, when they had, at the last General Election, no notion of what was coming upon them, I feel that we are bound, as guardians of their interests, to call upon the government to appeal to the people, and by the result of that appeal we will abide". The Lords rejected the Bill and Parliament was prorogued for ten weeks. Writing to Canon Malcolm MacColl, Salisbury believed that Gladstone's proposals for reform without redistribution would mean "the absolute effacement of the Conservative Party. It would not have reappeared as a political force for thirty years. This conviction ... greatly simplified for me the computation of risks". At a meeting of the Carlton Club on 15 July, Salisbury announced his plan for making the government introduce a Seats (or Redistribution) Bill in the Commons whilst at the same time delaying a Franchise Bill in the Lords. The unspoken implication being that Salisbury would relinquish the party leadership if his plan was not supported. Although there was some dissent, Salisbury carried the party with him.

Salisbury wrote to Lady John Manners on 14 June that he did not regard female suffrage as a question of high importance "but when I am told that my ploughmen are capable citizens, it seems to me ridiculous to say that educated women are not just as capable. A good deal of the political battle of the future will be a conflict between religion and unbelief: & the women will in that controversy be on the right side".

On 21 July a large meeting for reform was held at Hyde Park. Salisbury said in The Times that "the employment of mobs as an instrument of public policy is likely to prove a sinister precedent". On 23 July at Sheffield, Salisbury said that the government "imagine that thirty thousand Radicals going to amuse themselves in London on a given day expresses the public opinion of the day ... they appeal to the streets, they attempt legislation by picnic". Salisbury further claimed that Gladstone adopted reform as a "cry" to deflect attention from his foreign and economic policies at the next election. He claimed that the House of Lords was protecting the British constitution: "I do not care whether it is an hereditary chamber or any other – to see that the representative chamber does not alter the tenure of its own power so as to give a perpetual lease of that power to the party in predominance at the moment". On 25 July at a reform meeting in Leicester consisting of 40,000 people, Salisbury was burnt in effigy and a banner quoted Shakespeare's Henry VI: "Old Salisbury – shame to thy silver hair, Thou mad misleader". On 9 August in Manchester over 100,000 came to hear Salisbury speak. On 30 September at Glasgow he said: "We wish that the franchise should pass but that before you make new voters you should determine the constitution in which they are to vote". Salisbury published an article in the National Review for October, titled ‘The Value of Redistribution: A Note on Electoral Statistics’. He claimed that the Conservatives "have no cause, for Party reasons, to dread enfranchisement coupled with a fair redistribution". Judging by the 1880 results, Salisbury asserted that the overall loss to the Conservatives of enfranchisement without redistribution would be 47 seats. Salisbury spoke throughout Scotland and claimed that the government had no mandate for reform when it had not appealed to the people.

Gladstone offered wavering Conservatives a compromise a little short of enfranchisement and redistribution, and after the Queen unsuccessfully attempted to persuade Salisbury to compromise, he wrote to Rev. James Baker on 30 October: "Politics stand alone among human pursuits in this characteristic, that no one is conscious of liking them – and no one is able to leave them. But whatever affection they may have had they are rapidly losing. The difference between now and thirty years ago when I entered the House of Commons is inconceivable". On 11 November the Franchise Bill received its third reading in the Commons and it was due to get a second reading in the Lords. The day after at a meeting of Conservative leaders, Salisbury was outnumbered in his opposition to compromise. On 13 February Salisbury rejected MacColl's idea that he should meet Gladstone, as he believed the meeting would be found out and that Gladstone had no genuine desire to negotiate. On 17 November it was reported in the newspapers that if the Conservatives gave "adequate assurance" that the Franchise Bill would pass the Lords before Christmas the government would ensure that a parallel Seats Bill would receive its second reading in the Commons as the Franchise Bill went into committee stage in the Lords. Salisbury responded by agreeing only if the Franchise Bill came second. The Carlton Club met to discuss the situation, with Salisbury's daughter writing:

The three arch-funkers Cairns, Richmond and Carnarvon cried out declaring that he would accept no compromise at all as it was absurd to imagine the Government conceding it. When the discussion was at its height (very high) enter Arthur [Balfour] with explicit declamation dictated by G.O.M. in Hartington's handwriting yielding the point entirely. Tableau and triumph along the line for the ‘stiff’ policy which had obtained terms which the funkers had not dared hope for. My father's prevailing sentiment is one of complete wonder ... we have got all and more than we demanded.

Despite the controversy which had raged, the meetings of leading Liberals and Conservatives on reform at Downing Street were amicable. Salisbury and the Liberal Sir Charles Dilke dominated discussions as they had both closely studied in detail the effects of reform on the constituencies. After one of the last meetings on 26 November, Gladstone told his secretary that "Lord Salisbury, who seems to monopolise all the say on his side, has no respect for tradition. As compared with him, Mr Gladstone declares he is himself quite a Conservative. They got rid of the boundary question, minority representation, grouping and the Irish difficulty. The question was reduced to ... for or against single member constituencies". The Reform Bill laid down that the majority of the 670 constituencies were to be roughly equal size and return one member; those between 50,000 and 165,000 kept the two-member representation and those over 165,000 and all the counties were split up into single-member constituencies. This franchise existed until 1918.

He became Prime Minister of a minority administration from 1885 to 1886. In the November 1883 issue of National Review Salisbury wrote an article titled "Labourers' and Artisans' Dwellings" in which he argued that the poor conditions of working class housing were injurious to morality and health. Salisbury said "Laissez-faire is an admirable doctrine but it must be applied on both sides", as Parliament had enacted new building projects (such as the Thames Embankment) which had displaced working class people and was responsible for "packing the people tighter": "... thousands of families have only a single room to dwell in, where they sleep and eat, multiply, and die ... It is difficult to exaggerate the misery which such conditions of life must cause, or the impulse they must give to vice. The depression of body and mind which they create is an almost insuperable obstacle to the action of any elevating or refining agencies". The Pall Mall Gazette argued that Salisbury had sailed into "the turbid waters of State Socialism"; the Manchester Guardian said his article was "State socialism pure and simple" and The Times claimed Salisbury was "in favour of state socialism". In July 1885 the Housing of the Working Classes Bill was introduced by Cross in the Commons and Salisbury in the Lords. When Lord Wemyss criticised the Bill as "strangling the spirit of independence and the self-reliance of the people, and destroying the moral fibre of our race in the anaconda coils of state socialism", Salisbury responded: "Do not imagine that by merely affixing to it the reproach of Socialism you can seriously affect the progress of any great legislative movement, or destroy those high arguments which are derived from the noblest principles of philanthropy and religion".

Although unable to accomplish much due to his lack of a parliamentary majority, the split of the Liberals over Irish Home Rule in 1886 enabled him to return to power with a majority, and, excepting a Liberal minority government (1892 – 1895), to serve as Prime Minister from 1886 to 1892.

In 1889 Salisbury set up the London County Council and then in 1890 allowed it to build houses. However he came to regret this, saying in November 1894 that the LCC, "is the place where collectivist and socialistic experiments are tried. It is the place where a new revolutionary spirit finds its instruments and collects its arms".

Salisbury caused controversy in 1888 after Gainsford Bruce had won the Holborn by-election for the Unionists, beating the Liberal Earl Compton. Bruce had won the seat with a smaller majority than Francis Duncan had for the Unionists in 1885. Salisbury explained this by saying in a speech in Edinburgh on 30 November: "But then Colonel Duncan was opposed to a black man, and, however great the progress of mankind has been, and however far we have advanced in overcoming prejudices, I doubt if we have yet got to the point where a British constituency will elect a black man to represent them ... I am speaking roughly and using language in its colloquial sense, because I imagine the colour is not exactly black, but at all events, he was a man of another race". The "black man" was Dadabhai Naoroji, an Indian. Salisbury's comments were criticised by the Queen and by Liberals who believed that Salisbury had suggested that only white Britons could represent a British constituency. Three weeks later Salisbury delivered a speech at Scarborough, where he denied that "the word “black” necessarily implies any contemptuous denunciation. Such a doctrine seems to be a scathing insult to a very large proportion of the human race ... The people whom we have been fighting at Suakim, and whom we have happily conquered, are among the finest tribes in the world, and many of them are as black as my hat". Furthermore "such candidatures are incongruous and unwise. The British House of Commons, with its traditions ... is a machine too peculiar and too delicate to be managed by any but those who have been born within these isles". Naoroji was elected for Finsbury in 1892 and Salisbury invited him to become a Governor of the Imperial Institute, which he accepted.

Salisbury's government passed the Naval Defence Act 1889 which facilitated the spending of an extra £20 million on the Royal Navy over the following four years. This was the biggest ever expansion of the navy in peacetime: ten new battleships, thirty-eight new cruisers, eighteen new torpedo boats and four new fast gunboats. Traditionally (since the Battle of Trafalgar) Britain had possessed a navy one-third larger than their nearest naval rival but now the Royal Navy was set to the Two-Power Standard; that it would be maintained "to a standard of strength equivalent to that of the combined forces of the next two biggest navies in the world". This was aimed at France and Russia.

In the aftermath of the general election of 1892, Balfour and Chamberlain wished to pursue a programme of social reform, which Salisbury believed would alienate "a good many people who have always been with us" and that "these social questions are destined to break up our party". When the Liberals and Irish Nationalists (which were a majority in the new Parliament) successfully voted against the government, Salisbury resigned the premiership on 12 August. His private secretary at the Foreign Office wrote that Salisbury "shewed indecent joy at his release". Salisbury — in an article in November for the National Review entitled ‘Constitutional revision’ — said that the new government, lacking a majority in England and Scotland, had no mandate for Home Rule and argued that because there was no referendum only the House of Lords could provide the necessary consultation with the nation on policies for organic change. The Lords defeated the second Home Rule Bill by 419 to 41 in September 1893 but Salisbury stopped them from opposing the Liberal Chancellor's death duties in 1894. The general election of 1895 returned a large Unionist majority.

Salisbury's expertise was in foreign affairs. For most of his time as Prime Minister he served not as First Lord of the Treasury, the traditional position held by the Prime Minister, but as Foreign Secretary. In that capacity, he managed Britain's foreign affairs, famously pursuing a policy of "Splendid Isolation". Among the important events of his premierships was the Partition of Africa, culminating in the Fashoda Crisis and the Second Boer War. At home he sought to "fight Home Rule with kindness" by launching a land reform programme which helped hundreds of thousands of Irish peasants gain land ownership.

On 11 July 1902, in failing health and broken hearted over the death of his wife, Salisbury resigned. He was succeeded by his nephew, Arthur James Balfour. Salisbury was offered a dukedom by Queen Victoria in 1886 and 1892, but declined both offers, citing the prohibitive cost of the lifestyle dukes were expected to maintain. When Salisbury died his estate was probated at 310,336 pounds sterling. In 1900 Salisbury was worth £6.56 million, about £374 million in 2005 prices.

Salisbury is seen as an icon of traditional, aristocratic conservatism. The Conservative historian Robert Blake considered Salisbury "the most formidable intellectual figure that the Conservative party has ever produced". In 1977 the Salisbury Group was founded, chaired by Robert Gascoyne-Cecil, 6th Marquess of Salisbury and named after the 3rd Marquess. It published pamphlets advocating conservative policies. The academic quarterly Salisbury Review was named in his honour upon its founding in 1982. The Conservative historian Maurice Cowling claimed that "The giant of conservative doctrine is Salisbury". It was on Cowling's suggestion that Paul Smith edited a collection of Salisbury's articles from the Quarterly Review. Andrew Jones and Michael Bentley wrote in 1978 that "historical inattention" to Salisbury "involves wilful dismissal of a Conservative tradition which recognizes that threat to humanity when ruling authorities engage in democratic flattery and the threat to liberty in a competitive rush of legislation".

Not long before his death in 1967, Clement Attlee (Labour Party Prime Minister, 1945 – 1951) was invited to Chequers by Harold Wilson and was asked who he thought was the best Prime Minister of his lifetime. Attlee immediately replied: "Salisbury".

The 6th Marquess of Salisbury commissioned Andrew Roberts to write Salisbury's authorised biography, which was published in 1999.

After the Bering Sea Arbitration, Canadian Prime Minister Sir John Sparrow David Thompson said of Lord Salisbury's acceptance of the Arbitration Treaty that it was "one of the worst acts of what I regard as a very stupid and worthless life."

The British phrase 'Bob's your uncle' is thought to have derived from Robert Cecil's appointment of his nephew, Arthur Balfour, as Minister for Ireland .