Beginning with the Welsh title, which he won from Johnnie Owens in 1907, he went on to win the light-weight championship of England and Great Britain from Johnnie Summers, a success which carried with it the first gold challenge belt presented by lord Lonsdale. Three years later, in 1912, Welsh defeated Hughie Mehegan and won the championship of the British Empire and a second Lonsdale Belt to which he soon added a third by defeating Matt Wells for the light-weight championship of Great Britain, thus regaining the title he had lost to Wells in 1911. [Then, 1914, Welsh reached the top of his class by defeating Willie Ritchie for the light-weight championship of the World].

Welsh performed many remarkable feats of boxing. In 1907 he fought and knocked out three opponents in one day. These were Evan Evans (light-weight), Charlie Weber (welterweight), and Gomer Morgan (heavy-weight).

In later years Welsh lived in America and became a director of the ‘health farm’ at Bayside, Long Island. He was also director-in-chief of the physical training department, Walter Reed Army General Hospital, Washington, D.C. He d. 28 July 1927.