William Rees, also known as Gwilym Hiraethog, was an editor, prolific writer, Independent minister and influential radical leader. Hiraethog influenced Welsh politics both through the press and from the platform. He founded 'Yr Amserau', a Welsh liberal weekly, in Liverpool in 1843 and remained its editor until 1852. It was the first successful Welsh newspaper. Gwilym Hiraethog pleaded for the abolition of slavery in the U.S.A. chiefly through his book ‘Aelwyd F'ewythr Robert’, which was founded on Harriet Beecher Stowe’s ‘Uncle Tom's Cabin’.