Henry John "Harry" Cockayne-Cust was an English politician and editor who served as a Member of Parliament (MP) for the Unionist Party.
Cust was born to Sara Jane Cookson and Henry Cockayne-Cust, and was educated at Eton (where he was captain of the Oppidans) and Trinity College, Cambridge. While at Trinity College, he was elected to the Apostles and graduated with second-class honours in the Classical Tripos. Initially pursuing a legal career, Cust was admitted to the Inner Temple in 1888 but was not called. Instead he decided to enter Parliament, and won a by-election in 1890 for Stamford, Lincolnshire. He left Parliament during the general election, but returned five years later when he won a seat in the constituency of Bermondsey, remaining until 1906.
Cust was one of The Souls, and attached to Pamela Wyndham (who later married Edward Tennant). Others in the clique were Margot Asquith, Arthur Balfour, George Curzon, Alfred Lyttelton, Godfrey Webb, and George Wyndham. Considered a brilliant conversationalist by his contemporaries, he had a reputation as a womaniser and was the father of socialite and philanthropist Lady Diana Cooper, by the Duchess of Rutland,
though this was not acknowledged until much later. Cust was also
rumoured to be the natural father of Beatrice Stephenson Roberts, the
mother of British prime minister Margaret Thatcher,
and though there was no solid proof of this connection, Lady Diana
Cooper often jokingly referred to Mrs. Thatcher as her niece.
In 1892, Cust met with William Waldorf Astor, who invited him to edit Pall Mall Gazette.
Despite lacking any background in journalism, Cust accepted
immediately. He soon transformed the newspaper into the best evening
journal of the period, thanks in part to contributors such as Rudyard Kipling and H.G. Wells.
Yet Cust rejected contributions submitted by Astor (who had literary
aspirations); this, coupled with political disagreements, led to Cust's
dismissal in February 1896.
After leaving the Pall Mall Gazette, Cust continued his career as an author. He wrote several poems, most notably "Non nobis domine". During World War I Cust was active in propaganda on behalf of the British Government. In August 1914, he founded the Central Committee for National Patriotic Organizations. He died in 1917 of a heart attack at his home in Hyde Park Gate, London. He was heir to the barony of Brownlow, a position which at his death fell to his brother, Adelbert Salusbury Cust (b. 1867).