Fowkes was born in Lewisham, Kent, England, in 1894. He was educated at Dulwich College and Sandhurst. Brigadier Fowkes participated in the East African Campaign commanding 22nd (East Africa) Infantry Brigade, part of Lieutenant-General Alan Cunningham's force based in Kenya. In August 1941 he was placed in temporary command of the 12th African Division and was confirmed in the role the following month. In November he led his division, supported by Ethiopian patriot forces in the final action of the East African campaign, the capture of Gondar on 27 November.