Collection comprises correspondence with Philip Hammersley Leathes, manuscript papers, diaries, devotionals, dictionaries and pedigree rolls, title deeds and indentures, printed books and pamphlets, catalogues and the manuscripts of the architect, John Carter, [1350-1863]. Notably including correspondence from George Nayler of the College of Arms and Nicholas Carlisle, Secretary of the Society of Antiquaries, relating to publications of the Society, discoveries of antique brass plate, and the exchange of manuscripts between antiquaries, [1790-1838]; loose manuscript papers collected by Leathes, describing ornamentation in early printed devotionals, a fictional narrative entitled 'The amorous Jill: A tale', narrative of the Lisbon earthquake of 1755, notes relating to the observation of comets, including the comet of 1811, copies of charters of the reigns of Edward IV and Henry VII, papers relating to the Portland Vase, British Museum, fragments describing inscription on newly discovered brass plate, 1747-1829; pedigree rolls tracing the lineage of the English Crown, [1450, 1762]; manuscript volumes including collection of biblical extracts, liturgical handbook, autograph book with colour illustrations, antiquarian ephemera such as funeral memorials, armorials and the creation of nobles, volume by Francis Harrison entitled, 'The elements of navigation' with colour charts, tables and illustrations, dictionaries of Celtic and Saxon words, notes on the teaching of mathematics, commonplace book drawing on ancient and modern authors, manuscript diary including progress of architectural tour of Europe; title deeds and indentures for families in Nottingham, Southampton, London and Hungerford, residency certificates in Buckinghamshire and Northamptonshire, 1650-1751; printed books and pamphlets on the subjects of antiquarianism, genealogy and architecture, 1778-1853; manuscripts of John Carter, architect, acquired at his death in 1817 by his executor, Leathes, notably including autobiographical notebooks by Carter describing architectural subjects and tours, commonplace book, correspondence with Leathes, loose notes on linguistics and the ships of the Russia Company, obituaries of Carter and sale catalogue from his estate, 1700-1818; manuscript catalogues and display captions relating to the Leathes' papers, King's College London, 1819, 1837.

Papers of Edgar Prestage, 1881-1949, largely relating to his work on the history of Portugal, 16th-19th centuries. Letters to Prestage from various correspondents, 1886-1948 and undated, relate to a variety of subjects pertaining to his work, publications and translations, sources and interpretation, and also to acquaintances and contemporaries, other publications, and some personal matters such as correspondents' health and families, and include six letters from Fortunato de Almeida, 1917-1933 and undated; 24 letters from Joao Lucio de Azevedo, 1914-1933 and undated; 13 letters from Pedro Augusto de S Bartolomeu de Azevedo, 1910-1927 and undated; six letters from Henrique de Gama Barros, 1908-1925; five letters from Carlos Roma du Bocage, 1915-1918; three letters from Sir Richard Francis Burton, 1888-1889, and 12 letters from Lady Isabel Burton, 1894-1896, relating to Sir Richard's translation of Camoens; 22 letters from Julio de Castilho, 1908-1918; nine letters from Harold Castle, 1903-1906; six letters from Fidelino de Figueiredo, 1911-1918 and undated; eight letters from James Fitzmaurice-Kelly, 1905-1919; five letters from Anselmo Braamcamp Freire, 1905-1919; two letters from Pieter Geyl, 1923, 1926; letter from William Ewart Gladstone, 1893, congratulating Prestage on Letters of a Portuguese nun ; ten letters from Edward Heawood, 1922-1933; letter from Benjamin Jowett, 1887, explaining entrance examinations at Oxford; five letters from Margery Lane, 1927 and undated; six letters from Manuel de Oliveira Lima, 1910-1927; two letters, 1928, 1932, from Manuel II, King of Portugal, concerning the monarch's bibliography of early Portuguese books; eight letters from Jacinto Octavio Picon, 1911-1920; seven letters from Jacinto Inacio de Brito Rebelo, 1895-1908; eight letters from Jaime Batalha Reis, 1894-1896, 1904-1905, 1922; 12 letters from Francisco Rodrigues, 1913-1918, 1930 and undated; two letters from John Ruskin, 1886 and undated, on the study of architecture; seven letters from Antonio Maria Jose de Melo Cesar e Meneses, 5th Conde de Sabugosa, 1905-1913; five letters from Luis Teixeira de Sampayo, 1921-1928; letter from Herbert Louis Samuel, 1st Viscount Samuel, 1905, congratulating Prestage on Eca de Queiroz's The sweet miracle ; five letters from Georg Schurhammer, 1930-1936; five letters from Wilhelm Storck, 1894-1895; five letters from Herbert Thurston, 1905-1913; ten letters from Pedro Tovar de Lemos, 2nd Conde de Tovar, 1916-1927 and undated; 13 letters from Carolina Michaelis de Vasconcellos, 1895-1896, 1907-1922, and 11 letters from her husband, Joaquim de Vasconcellos, 1897, 1908-1925; six letters from Afonso Lopes Vieira, 1910, 1914, 1927 and undated; five letters from Tomas Maria de Almeida Manuel de Vilhena, 8th Conde de Vila Flor, 1925-1929 and undated; letter from Oscar O'Flahertie Wills Wilde, [1892], regretting he cannot send a copy of his unnamed play (perhaps Lady Windermere's Fan ) as it has not yet been published. There is also a letter of 1881 from Antonio Candido Goncalves Crespo to Maria Amalia Vaz de Carvalho (father and mother of Prestage's wife). Ephemera includes signatures of Gomes Eannes Azurara, William Wordsworth, [? Isaac] Disraeli and Samuel Wilberforce; Christmas cards; the visiting card of S T P Kruger, President of the Transvaal Republic, 1903; menus, including the House of Commons Coronation luncheon in Westminster Hall, 1902; a ticket to the coronation of Edward VII, 1902; and an invitation to a party at Windsor Castle, 1912. Otherwise the collection comprises research notes and transcriptions on various subjects and sources, including Restoration period Portugal; Sousa Coutinho; Portuguese in Africa, Brazil and Asia; the War of the Spanish Succession; 17th century Portuguese history, including diplomacy; the sermons of Father Antonio Vieira SJ; Portuguese bibliographies prepared by Prestage; annotated typescripts on the Portuguese in Abyssinia down to 1543, aspects and results of Portuguese colonisation, and Portuguese reminiscences (1948); Prestage's 'The Mode of Government in Portugal during the Restoration Period'; photographs of Portuguese fortresses in Morocco; notebook on 'Analyse das "Cartas Familiares" '; copies of letters of F de Sousa, including his embassies to France and Rome; copies of letters of Sir R Southwell, English ambassador to Lisbon; material relating to relations between Spain and Portugal; pamphlets and articles of Prestage; proofs for a chapter entitled 'L'Intevention Anglaise dans la Peninsule Iberique', in an envelope addressed to Prestage and labelled 'D Fernando & the Holy See by E Perroy'.