The Bee Gees are British.
I struggle with this. I'm never sure whether they are or not. Certainly born British, Barry 14 and the twins 11 when they migrated in 1960. First recordings in Australia by the time Barry was 21 Robert Stigwood had them back in Britain.
Wikipedia lists Barry as 'British/American'.
I don't have strong opinions either way but it does frustrate my cataloguing.
Arguably Cliff Richard is Indian, AC/DC are British, Freddie Mercury Tanzanian, Jackson Browne German and Marcia Hines American.