Douglas Valder Duff was born in Rosario de Santa Fe in the Argentine where his father, Arthur Joseph Duff, was the British Consul. He was the eldest son of Arthur andhis wife Florence, nee Valder. His godfather was Roger Casement who later became notorious by being hanged for treason in the First World War.
He wrote over 80 books under his own name and also used the pseudonyms Douglas Stanhope, Alan Paxton, Leslie Savage, Peter Wicklow and 'Mainsail'.