Born in Southend-on-Sea, Essex, into a family of physicians, Warwick Deeping was educated at Merchant Taylors' School. He proceeded to Trinity College, Cambridge, to study medicine and science (receiving his MA in March 1902), then went to Middlesex Hospital to finish his medical training. During the First World War, he served in the Royal Army Medical Corps. Deeping later gave up his job as a physician to become a full-time writer. He married Phyllis Maude Merrill and lived for the rest of his life in "Eastlands" on Brooklands Road, Weybridge, Surrey.