The number of Welsh speakers has remained pretty static over the last 200 years. In the Glamorgan valleys, most of the population spoke Welsh, but was pretty sparse. The coal boom brought workers flooding in, but the actual number of Welsh speakers did not go down. Drive through Llanelli (or Pontardawe) and up to North Wales, and you will find people speaking Welsh - the more so once you get to the Llyn peninsula. Have you been misled over the Welsh language?