Born Kathleen Annie Josephine Madden, she is the only daughter of banker Paul J. Madden, who is Mayor of Cork in 1885–1886 and a friend of Charles Stewart Parnell, and Eliza Madden (née Dwyer). She is educated privately at her family home, Wood’s Gift, Blackrock Road.
By the end of the 19th century Madden is contributing short stories to various British and American publications, such as The Pall Mall Magazine, Blackwood’s Edinburgh Magazine, Harper’s Magazine, The Windsor Magazine and others.
On February 16, 1901, five weeks after her father’s death, she marries the writer Ernest Temple Thurston. They separate in 1907 and are divorced in 1910 on grounds of his adultery and desertion. The suit goes undefended. Thurston “complained that she was making more money by her books than he was, that her personality dominated his, and had said that he wanted to leave her.”
Thurston’s novels achieve success in Britain and the United States. Her best-known work is a political thriller entitled John Chilcote, M.P. (as The Masquerader in the United States), published in 1904 and on The New York Times bestseller list for two years, ranking as third best-selling book for 1904 and seventh best in 1905. Her next book, The Gambler, comes out in 1905 and it too makes the U.S. best-selling lists for that year. This is the first time The New York Times had recorded any author, female or male, as having two top-ten books in a single year. In 1910, she is back on the same list at No. 4 with her novel Max, the story of a young Russian princess, who flees disguised as a boy to the Montmartre Quarter of Paris, on the night before her arranged marriage.
John Chilcote, M.P. is adapted for the stage by John Hunter Booth and opens on Broadway in 1917. It is filmed four times, the first silent film by American Pathé in 1912 under the title The Compact and starring Crane Wilbur. The second film is a 1920 Russian/French co-production entitled Chlen parlamenta. Two more films are made using the American book title The Masquerader, in 1922 and then by The Samuel Goldwyn Company in 1933 as a “talkie” starring Ronald Colman.
An epileptic, Thurston’s blossoming career is cut short at the age of 36 when she is found dead in her hotel room in Cork on September 5, 1911. The official enquiry the following day gives the cause of death as asphyxia as result of a seizure. She had been due to remarry later in the month to Dr. A. T. Bulkeley Gavin. She is buried in St. Joseph’s Cemetery, Cork. The story of her final years and her relations with Bulkeley Gavin are the subject of a published thesis by C. M. Copeland, written while studying at the Napier University, Edinburgh.