Most people in Wales know that some children in the nineteenth century were victims of the Welsh Not, a wooden board hung around the necks of children who were heard speaking Welsh. Use of the Welsh Not was often followed by a physical punishment, and it is often named as a key reason for Welsh decline. Despite how well-known the Welsh Not is, this is the first study that interrogates where, when, and why it was used. This book is an account of the different ways children were punished for speaking Welsh in nineteenth-century elementary schools and the consequences of this for children, communities, and the linguistic future of Wales. It shows how the exclusion of Welsh hindered pupils from learning English, the very thing it was meant to achieve. Thus, gradually over the century, Welsh came to be used more and more in schools, making them a more effective mechanism in the Anglicization of Wales.