Cosmopolitan Club (act. 1852–1902), was founded in 1852 among a group of friends who met regularly in the diplomatist Robert Morier's rooms at 49 Bond Street, London, and decided to expand their coterie into an exclusive social club. About 1854 they leased rooms at 30 Charles Street, Berkeley Square, previously the studio of the artist George Frederic Watts, and then of Henry Wyndham Phillips, the club's honorary secretary. The club was limited to 150 members who paid 3 guineas a year. Blackballing was avoided by having the names of candidates for membership circulated to all members, who could checkmark as many of their choices as there were vacancies: those attracting the most votes were elected.

The club was open only twice a week, on Wednesdays and Sundays from 10 p.m. to 2 a.m. Its premises were distinctive—one large room with a lofty ceiling and skylight, dominated by a gigantic painting left by Watts of a naked damsel in distress. At the entrance was a huge folding screen, each panel depicting a different form of Chinese torture. Ranged around the fireplace was an inner circle of sofas; behind them were tables bearing coffee, tea, various bottles of spirits, clay pipes, and a jar of Turkish tobacco. Unlike the cavernous Pall Mall clubs where silence and privacy ruled, the Cosmopolitan was dedicated to conviviality and conversation. Its members all knew one another, and were encouraged to invite interesting guests, particularly foreign visitors. It was the most important of Anthony Trollope's several clubs to the writing of his Palliser novels, appearing in Phineas Redux as 'the Universe', the club where the best informed political gossip is heard. In the words of the novelist Henry James, several times a guest, it was 'a talking club, extremely select' (Edel, 30).

The higher journalism was well represented in the club. Members connected with The Times, then at the peak of its influence, included its assistant editor George Dasent, Robert Lowe, George Venables, Henry Reeve, Matthew Higgins, Laurence Oliphant, Moberley Bell, Tom Taylor, W. V. Harcourt, and William Cornwallis Cartwright. Saturday Review contributors included Francis Palgrave, Julian Fane, Mountstuart Grant-Duff, T. H. Huxley, Harcourt, and Venables. The latter three members were Cambridge Apostles, as were Taylor, Monckton Milnes, Alfred Tennyson, James Spedding, and Edward Stanley (fifteenth earl of Derby). The club provided W. M. Thackeray the sort of gentlemanly contributors he sought for his Cornhill Review, as well as its most notable illustrators, John Millais and Frederic Leighton. Its publisher, George Smith, famous for his generous contracts, was a member, as were several of his most noted authors, including John Ruskin, Robert Browning, and Trollope. Frederick Greenwood, editor of Smith's gentlemanly newspaper the Pall Mall Gazette, recruited contributors from among such fellow members as Ruskin, Huxley, Higgins, and Milnes. The publisher John Blackwood was a member, as were several of his authors, and contributors to Blackwood's Magazine such as Oliphant. Other editors included James Anthony Froude of Fraser's Magazine, Edward Dicey of the Daily News and The Observer, Frank Hill of the Daily News, Trollope of Saint Pauls, Taylor of Punch, and Reeve and his successor Arthur Elliot of the Edinburgh Review.

Well-placed civil servants were a prominent contingent in the club, among them Morier, Algernon West, Ralph Lingen, Robert G. W. Herbert, Reginald Welby, Charles Rivers Wilson, Palgrave, Reeve, Spedding, Taylor, and Trollope. A number served as private secretaries to leading political figures, chiefly Liberal—West, Herbert, Palgrave, and Edward Hamilton to Gladstone, Evelyn Ashley to his stepgrandfather Lord Palmerston. Ashley exploited his position by publishing The Owl, an insiders' newspaper that circulated among the smart set in the 1860s. Henry Drummond-Wolff, A. W. Kinglake, Oliphant, and Dasent were members who contributed to its gossip-rich columns.

Although the Cosmopolitan had no explicit political affiliation its membership was decidedly Gladstonian Liberal. Many held office under Gladstone, including most of his first three cabinets—lords Granville [see Gower, Granville George Leveson-], Kimberley [see Wodehouse, John], Northbrook [see Baring, Thomas George], Goderich (later Ripon) [see Robinson, George Frederick Samuel], Derby, and Rosebery [see Primrose, Archibald Philip], Lowe, John Bright, W. E. Forster, Henry Bruce, Chichester Fortescue, G. J. Goschen, Joseph Chamberlain, Harcourt, and Farrer Herschell. Many club members were significantly involved in the education issue, including three clergymen, Frederick Temple (the future archbishop of Canterbury), William Rogers, and William Henry Brookfield, as well as Forster, Lingen, Lowe, Palgrave, Walter Severn, Granville, and several who taught at F. D. Maurice's Working Men's College, Thomas Hughes, Grant-Duff, Lord Goderich, Frederic Harrison, and Ruskin.

Foreign and colonial policy was another area of club expertise. Granville, Derby, Rosebery, Kimberley, and Lord Lansdowne [see Fitzmaurice, Henry Charles Keith Petty-] served as foreign secretary. Five successive viceroys of India, lords Northbrook, Lytton, Ripon, Dufferin [see Blackwood, Frederick Temple Hamilton-Temple-], and Lansdowne, were club members, as was Lord Lawrence. Others with specialist knowledge on Eastern matters included A. H. Layard, Kinglake, Oliphant, Henry Loch, Grant-Duff, Dicey, Bell, James Wilson of The Economist, and Edward FitzGerald, translator of the Rubáiyát of Omar Khayyám. Froude, Herbert, and Trollope had imperial expertise. Some notable military members who won honours in imperial warfare were lords Clyde [see Campbell, Colin], Sandhurst [see Mansfield, William Rose], and Wolseley, Sir Anthony Sterling, Sir James Outram, Sir Redvers Buller, and the soldier–scholar Sir Henry Rawlinson. The African explorer John Hanning Speke was a member.

The club's strong artist contingent owed much to Watts and Phillips, who was also secretary of the Artists' General Benevolent Institution, as well as to the influence of Thackeray and Ruskin. The club's skylit premises were occasionally used for daytime public art exhibitions such as one in which Ruskin's protégé John Inchbold and other artists showed works refused by the Royal Academy. Artist members also hung some of their own work in the club. Another Ruskinian was the civil servant–artist Severn who founded the Dudley Gallery, while R. B. Martineau was a founding member of the strongly Pre-Raphaelite Hogarth Club. Friends of Thackeray with Pre-Raphaelite links were the club's two future presidents of the Royal Academy, Leighton and Millais. The much-honoured Watts's role as chief portrait artist of the nation's great men was facilitated by his club membership. Two sculptors who succeeded in attracting major commissions and becoming RAs, Thomas Woolner and Carlo Marochetti, were members, as was the well-connected architect Philip Hardwick, treasurer of the Royal Academy. Tom Taylor and Palgrave were both influential art critics, and the wealthy collector Sir William Stirling-Maxwell was an expert on Spanish art. Representatives of the stage were fewer, though the gentlemanly actor Horace Wigan and Henry Irving were members. The ubiquitous Taylor was also a successful playwright. Scientists were even rarer though Huxley was a member, as were two fashionable physicians, Sir Richard Quain and Sir William Priestley. The prince of Wales [see Edward VII] joined the club about 1865.

Something of the Cosmopolitan Club's atmosphere is conveyed by visitors' impressions. Benjamin Moran, assistant secretary in the American embassy, was impressed by the pictures that filled the walls and noted that guests enjoyed full privileges in this 'most social club in London' (Moran, 1009), including free drinks and tobacco, and were freely engaged in conversation by members. Arthur Munby in his diary describes the club in full spate at midnight with vivid sketches of some of its notables, including a drunken Monckton Milnes assuring him that membership of the Athenaeum Club was 'unm'stak'l sign'idiocy', and less notables—'several of those amiable young gentlemen with downy moustaches who condescend to represent mankind in Parliament' (Hudson, 25). Although Thackeray characteristically joked that 'everyone goes there with his white choker at midnight, to appear as if he had just been dining with the aristocracy' (Ray, 330), many members were dedicated diners-out who came to the club fresh from West End tables to exchange the latest gossip. One such member was Edward Hamilton, whose diary indicates that the club was still thriving in the 1880s. But the strains of the Liberal split over home rule may have told on the club, or perhaps it faded with its founding generation. It dissolved shortly after migrating to rooms in the Alpine Club in 1902.