Born in Williamsburg and educated at the Cornwall Grammar School, Whitney was called to the Bar in 1876. He was elected to the legislative assembly as Conservative member for Dundas in 1888. A noted orator, he was leader of the opposition 1896-1905. In the latter year the Liberal government headed by the Hon. G.W. Ross was defeated and Whitney became the sixth prime minister of Ontario. He held that post 1905-14 and his administration was noted for its introduction of extensive legislation relating to agriculture, labour, education and public utilities. Whitney received his knighthood in 1908.