Leonard Patrick O'Connor Wibberley (9 April 1915 – 22 November 1983), who also published under the name Patrick O'Connor, among others, was a prolific and versatile Irish author who spent most of his life in the United States. Wibberley, who published more than 100 books, is perhaps best known for five satirical novels about an imaginary country Grand Fenwick, particularly The Mouse That Roared (1955).
Wibberley's adult and juvenile publications cut across the categories of fictional novels, history, and biography. He also wrote short stories (several published in The Saturday Evening Post), plays and long verse poems. Some of his books are in series. Besides the 'Mouse' series, as Leonard Holton, he created the eleven-novel 'Father Bredder' mystery series (basis of a television series, Sarge) about "a major figure in the clerical crime drama". Among his more than 50 juvenile books are (with Farrar, Straus and Giroux), a seven-volume 'Treegate' series of historical fiction and a four-volume life of Thomas Jefferson. As Patrick O'Connor, he wrote the Black Tiger series on auto racing, for young adults. Wibberley is also classified as a science fiction writer.
Throughout the decades, scenes and senses of the sea play important parts in both Wibberley's fiction and nonfiction. Three of his novels have been made into movies: The Mouse That Roared (1959), The Mouse on the Moon (1963), and The Hands of Cormac Joyce (1972).
Wibberley died of a heart attack in Santa Monica, California, aged 68, on 22 November 1983.