William Warren Lynch was born on September 30, 1845, in Bedford, Quebec.

He was a lawyer, politician, and judge. He attended Stanbridge Academy and the University of Vermont in Burlington. He received a scholarship from McGill College in 1862 but had to abandon his studies because of poor health. He worked on the family farm while teaching locally and in 1865, he returned to McGill College to study law. He graduated in 1868 (BCL) with the Elizabeth Torrance Gold Medal for excellence in Roman law and was called to the Quebec bar. In 1869, he started practicing law in Knowlton and later in Sweetsburg. In 1870, he became editor of the Cowansville Observer. He was also Mayor of the Township of Brome, and Warden of the county. In 1871, he was acclaimed to the Legislative Assembly of Quebec for the electoral district of Brome and moved to Knowlton. A Conservative, he was acclaimed in 1875 and re-elected in 1881 and 1886. He was Solicitor-General in the cabinet of Joseph-Adolphe Chapleau and later was appointed commissioner of railways and commissioner of crown lands. He was made a Queen's Counsel by the Quebec government in 1879 and the Federal government in 1881. In 1889, he was appointed a Judge of the Superior Court for the District of Bedford. He received honorary doctorates from Bishop’s College in 1883 and McGill University in 1904.

In 1874, he married Ellen Florence Pettes (1850–1926). He died on November 23, 1916, in Knowlton, Quebec.