 Pakatanga Hondo yeGirisi neTurkey muna April 1897, Callwell akapinzwa muchiuto cheGirisi uye akapedza gore muNear East. Muna October 1899, apo hondo yakaziviswa kuBoer RepublicsMuSouth Africa, Callwell akagadzwa mudare raSir Redvers Buller, uye aivepo panguva yese yekuita iyo yakaguma nekununurwa kweLadysmith musi wa 28 Kukadzi 1900. Muna Gunyana 1901 akagamuchira kutaurwa mumakadhi kubva kuna Earl Roberts, uye akapihwa chinzvimbo chebrevet che lieutenant-colonel ine zuva ra29 Mbudzi 1900, uye akapiwa rairo yekoramu inofamba, iyo yaakashanda nayo muWestern Transvaal uye muCape Colony kusvika pakupera kwehondo muna Chikumi 1902. Akabva kuCape Town achienda kuEngland mwedzi wakatevera, ndokusvika kuSouthampton muna August 1902. 