most of whom can't accept that this is a part of Britain where the first language is not English.
The most convenient source of statistics to hand is a survey published by the Welsh Office, Arolwg Cymdeithasol Cymru 1992: adroddiad ar y Gymraeg published about March 1995. It showed that 21.5% of the population of Wales (590800 people) speak Welsh; this divides into 32.4% of 3-15 year olds, 17.8% of 16-29s, 16.7% of 30-44s, 18.7% of 45-64s and 24.2% of over 65s. 55.3% of them (326600, 12% of the population) are first-language speakers, meaning someone who spoke more Welsh than English as a child at home. 13.4% of the population of Wales claims to be fluent in Welsh, and 66.1% claim no knowledge of Welsh at all.
So the main language in Wales is English, and the minority speak Welsh.