Haddon studied at the Slade School from 1883 under Professor Alphonse Legros and in Madrid, 1886-87. On his return to England, he worked with Sir Hubert Herkomer from 1888-90. Haddon lived and worked in Rome in 1896-7. Exhibited at the principal London galleries from 1883 including 12 works at SS, 1883-90, including ‘A Country Hack’, ‘The Cabbage Garden’ and ‘Berkshire Meadows’. Also exhib. At the RA, including views in Spain and portraits, and at the NWS. He was elected RBA in 1896 and had several one-man shows in London in the early 1900’s, including the Leicester Galleries (1902), Chenil Gallery (1906) and the Chenil Galleries ((1908). Travelled extensively from 1926 – 1930 Canada, U.S.A, Hawaii, South Pacific, Lived mainly in London and later, in Cambridge, where he died on 13th December 1941, aged 77.