Director, National Portrait Gallery, London, 1895-1909, and co-editor of the Burlington Magazine, 1909-1919. Cust's father was the barrister Sir Reginald John Cust (1828-1913) and mother Lady Elizabeth Caroline Bligh (Cust) (1830-1914). After graduating from Eton College he attended Trinity College, Cambridge (1877-1881) completing a degree in Classics. Initially assigned to the War Office between 1882 he made a civil-service transfer to the Department of Prints and Drawings at the British Museum under Sidney Colvin in 1884. Though Cust had been a poor performer in the War Office, he shone in the Department under Colvin. Cust set about creating an Index to the Dutch, Flemish, and German artists represented in the print room (published in 1893) and started another for the French artists. In 1895 Cust succeeded George Scharf as director of the National Portrait Gallery and married Sybil Lyttelton (1873-1934), a noble and half-sister the politician Alfred Lyttelton (1857-1913). The following year his index of French artists for the British Museum was published. As Portrait Gallery director, Cust moved the collection from the temporary quarters at Bethnal Green to the modern space at St. Martin's Place. He issued the first of two permanent holdings catalogs of the collection in 1896. A study of Dürer's paintings and prints appeared in 1897, and a book on an German engraver, Master E. S. in 1898. Also in 1898, Cust produced a History of the Society of Dilettanti. Running a state portrait gallery required broad and specific knowledge of peerage and genealogy as well as a knowledge of the private holdings of country estates. Cust mastered all of this, a knowledge resulting in numerous contributions to the Dictionary of National Biography. In 1900 he published a large book on Anthony van Dyck. Cust added duties as the surveyor of the king's pictures to his Director position in 1901, rehanging most of the pictures in the Royal palaces. A smaller treatment on van Dyck and a book on the The Bridgewater House Gallery were both issued in 1903. Under the auspices of the Oxford Historical Society, Cust wrote catalogs of the portrait collections for three consecutive years beginning in 1904. A book of his personal poems, Ludibrium ventia, was privately published in 1904. His catalog of the royal collection, The Royal Collection of Paintings: Buckingham Palace appeared in 1905 with a second volume on Windsor Castle in 1906. In 1909, he resigned from the Portrait Gallery (succeeded by C. J. Holmes), and joined Roger Fry as joint editor of the Burlington Magazine beginning in 1909, a relationship that lasted ten years. At the magazine, he supplied book reviews and articles on portraiture, raising public interest in this neglected genre. Almost immediately he was embroiled in the "Flora Bust" scandal, helping the magazine to denounce as modern a bust of the goddess Flora purported to be a Leonardo and purchased by another member of the Burlington Magazine's Consultative Committee, Wilhelm Bode for his Berlin museum. Bode resigned from the committee in protest. In 1913 Cust published a study of the painter Hans Eworth (fl. 1540-73) ("H. E.") reassigning many works to him in the Walpole Society's Annual for that year. Cust and the Burlington's other joint editor, More Adey, developed strong disagreements with Fry and both resigned from the magazine in 1919. In 1927 he relinquished his role as surveyor of the king's pictures, replaced by C. H. Collins Baker, and named as a KCVO, Knight Commander of the Royal Victorian Order, a member of the second highest rank of a British order of knighthood. He died at home, Datchet House, Datchet, Buckinghamshire. His cousin was the historian of Italian art, Robert H. Hobart Cust. Cust was responsible for raising the interest of British portraiture to an international level and helping to introduce northern artists to British attention. Before Cust's writing in the Burlington Magazine, English art historians had focused largely on Italian artists. His early monographs on Van Dyck and Dürer were widely read. Though Cust lacked an elegant writing style, his work was redeemed by a scrupulous attention to facts. He demolished many myths around the art he wrote. His re-analysis of the sixteenth-century painter Hans Eworth, long erroneously identified with Lucas d'Heere, is of permanent significance.
- Lionel Cust notes and correspondence, ca. 1920., Getty Research Institute. https://primo.getty.edu/permalink/f/19q6gmb/GETTY_ALMA21126858470001551, 86-A885.
- NPG - Papers of Sir Lionel Cust, National Portrait Gallery. https://archiveshub.jisc.ac.uk/data/gb1082-npg8, GB 1082 NPG8.