1802-1883. Welsh Congregational minister, author, and social leader, better known by his pen name, “Gwilym Hiraethog.” Born at Llansannan, Denbighshire, Rees obtained his only formal education in a few terms at the local school. He spent his early years as a farm laborer and shepherd. This did not prevent him from acquiring a considerable amount of the literary culture that was available to him in the Welsh language. He became a Congregational minister and served at Mostyn (1831-37); Denbigh (1837-43); Tabernacle, Liverpool (1843- 53); and Salem, Liverpool, until his retirement in 1875. Rees provides the most vivid example of the way in which evangelical Christianity in its Calvinistic form inspired cultural and political activity of a radical kind in nineteenth-century Wales. He was one of the most powerful preachers of the midcentury and no mean theologian when it is recalled that he had no formal training in its study. His little catechism (Y Cyfarwyddwr, 1833) proved popular and influenced the minds of many young people. He wrote a treatise on natural and revealed religion in 1841, most of which is devoted to an exposition of the divine authority of Scripture.
Like many Victorians, Rees was a man of boundless energy. He published a vast amount of poetry-his hymn “Dyma gariad fel y moroedd” became a kind of “signature-tune” during the 1904-5 Welsh Revival-but much the greater part of his work has not survived the test of time. His prose works are now of more interest, and in this field again he was a prolific author. His most influential work was done as an editor. He edited the newspaper Yr Amserau (“The Times”) from 1843 to 1852, and in articles cast in the form of an old countryman's letters he introduced the main themes of radical politics to Welsh readers. He was also one of the founding fathers of modern Welsh nationalism. He corresponded with the Italian patriot Mazzini, and a Hungarian deputation visited him to express gratitude for the support he had given Kossuth.was one of the key figures in linking the evangelical churches of Wales with what later became Liberalism, but unlike that of some of his contemporaries, his theological and religious enthusiasm was not overshadowed by social interests.
See E. Rees, Memoir of William Rees (1915).