Corbet, William Joseph (1824–1909), civil servant and politician, was the third son of Robert Corbet of Ballykaneen, Queen's County, and his wife, Alice, daughter of John Mulhall of Clonaslee, where William Corbet was born on 12 December 1824. He was educated at Broadwood Academy in Lancashire. His career was mainly in the Irish 'lunacy office', as a clerk (1847–53) and as chief clerk (1853–77). He lived at Spring Farm, Kilquade, Co. Wicklow, and for many years was a friend of Charles Stewart Parnell (qv), accompanying him on shoots at Aghavanna. Later, as home rule MP for Co. Wicklow (1880–85) and for the new East Wicklow division (1885–92), he became a close political colleague of Parnell. Corbet headed the large number of supporters who on 15 December 1881 ploughed and manured Parnell's farm at Avondale during his detention for Land League activities. It was the first of several such operations between then and January 1884. With Parnell he successfully pressed for a Wicklow harbour scheme (1880) and then for a similar scheme at Arklow. Continuing to support Parnell after the split in his party in December 1890, he was defeated at the elections of 1892 but was reelected in 1895; he finally retired in 1900.
A political moderate, Corbet was the author of several articles and pamphlets. He also wrote verse, notably Songs of my summer-time (1864, under the pseudonym Harry Wildair), The battle of Fontenoy (1871), and pieces on the Moore centenary (1879) and on the visit to Ireland of the empress of Austria (1879). He became a member of the Statistical and Social Inquiry Society in 1863 and the RIA in 1878. To the former he read a paper, ‘On the statistics of insanity’, in 1874. He was a sportsman from childhood and owner of a famous breed of Irish red setters.
In 1865 he married Elizabeth, daughter of Richard Jennings; she died five years later. In 1890 he married Marie, daughter of David Fitzhenry. W. J. Corbet died 1 December 1909 at his home, leaving a son William. A memorial to him is in Kilquade catholic church.