During the first half of the twentieth century several societies and voluntary organizations – some short-lived and others still existing – reacted to the dangers facing the Welsh language. They worked among members of all social classes, in all areas and in each social domain in order to ensure the continuation and prosperity of the Welsh language, and created firm foundations for the growth of the language movement after the Second World War. This paper focuses on the history of the National Union of Welsh Societies and Urdd Gobaith Cymru Fach. In 1913 around seventy local Welsh societies were united under the wing of the National Union of Welsh Societies and local and national campaigns were organized in order to raise the status of the Welsh language in the fields of education, publishing and the law. Established in 1922, the youth movement Urdd Gobaith Cymru Fach, which still exists, was a completely different organization. It strove to ensure that the essential elements of Welsh culture, such as literature and song, were passed on to the younger generation. Young people were also introduced to games, sports, spoken films and summer camps through the medium of the Welsh language.