That would be a personal choice as you could use either as your nationality. A Welsh nationalist is likely to choose Welsh while a non Welsh speaker who is a supporter of the United Kingdom might choose British.
Welsh and British
The actress Eve Myles is from the country of Wales. However her nationality is half British and half Welsh. She was born in Ystragynlais of United Kingdom.
British. Born in London raised in Wales
Welsh - he was born in Buckley (near the English border) in 1980, and has gone on to win 8 caps for Wales.
Christian Bale was born in Wales but considers himself English. Timothy Dalton was born in Wales and also says the same. Tom Jones is 25% Welsh ancestry and considers himself Welsh.
British - Welsh, born in Swansea [1914] and died in the USA [1953] of alcoholic abuse on a lecture tour.
Welsh
Welsh people are born in the country of Wales which is part of the United Kingdom (UK). Click on the link below for more information on Wales
Jimmy Wales was born in Huntsville, Alabama, and is American.
Scotland Another answer There is no "hometown" for Welsh people. The Welsh are people who were born and live in the country of Wales which is part of the United Kingdom of Great Britain and Northern Ireland. The people of what is now Wales are descendants of the ancient Celtic tribes who occupied the British Isles before the Roman Invasion.
Australian, but born in wales
Imogen Mary Thomas is Welsh. She was born November 29, 1982 in Gorseinon, Wales. She first started working as a model when she was thirteen years old.