Ethel Lilian Voynich, née Boole (May 11, 1864, County Cork, Ireland - July 27, 1960, New York City) was a novelist and musician, and a supporter of several revolutionary causes. Her father was the famous mathematician George Boole. She was married to Wilfrid Michael Voynich who is the eponym of the Voynich manuscript.
She is most famous for her novel The Gadfly, first published in 1897 in the United States (June) and Britain (September), about the struggles of an international revolutionary in Italy. This novel was very popular in the Soviet Union and was the top best seller and compulsory reading there, and was seen as ideologically useful; for similar reasons, the novel has been popular in the People's Republic of China as well. By the time of Voynich's death The Gadfly had sold an estimated 2,500,000 copies in the Soviet Union.
In 1955, the Soviet director Aleksandr Fajntsimmer adapted the novel into a film of the same title (Russian: Ovod). Composer Dmitri Shostakovich wrote the score (see The Gadfly Suite). The Romance, a segment from this composition, along with some other excerpts, has since become very popular.
According to historian Robin Bruce Lockhart, Sidney Reilly — a Russian-born adventurer and secret agent employed by the British Secret Intelligence Service — met Ethel Voynich in London in 1895. Ethel Voynich was a significant figure not only on the late Victorian literary scene but also in Russian émigré circles. Lockhart claims that Reilly and Voynich had a sexual liaison and voyaged to Italy together. During this scenic tarriance, Reilly apparently "bared his soul to his mistress," and revealed to her the story of his strange youth in Russia. After their brief affair had concluded, Voynich published in 1897 her critically acclaimed novel, The Gadfly, the central character of which, Arthur Burton, was allegedly based on Sidney Reilly's own early life. However, Andrew Cook, a noted biographer of Reilly, disputes Lockhart's romanticized version of such events to be doubtful and counters instead that Reilly was perhaps informing on Voynich's radical, pro-émigré activities to William Melville of the Metropolitan Police Special Branch.