There is no record of William Hague being fluent in any language other than English which he speaks with a Yorkshire accent. However, his Welsh born wife taught him how to sing the Welsh national anthem in Welsh.
Wales is Welsh. Welsh isn't spoken as much as it used to be in Wales, especially South Wales, but in the northern parts of the country there are much more people who speak Welsh as their first language. Wales is a part of the United Kingdom. Wales.