Born in London. Studied at the Regent Street Polytechnic of Art in 1907-10, then at Royal College of Art in 1910-13. In 1922 held first solo exhibition at Chenil Galleries. The 1920's were very busy for Underwood, he travelled extensively in Mexico and Spain. In 1931 founded and published the magazine 'Island', to which such artists as Henry Moore and Eileen Agar contributed. In 1969 retrospective exhibition took place at Minories, Colchester. National Museum of Wales, Cardiff put on a show 'Mexico and after' in 1979. Tate Gallery holds his work. (see Art UK)