Kammala jumla mai zuwa: Bayan kwana biyar kawai, tare da barkewar Yaƙin Boer, an ba Knox umurnin Brigade na 13 na Infantry a kan aikin da aka yi na 6th Division karkashin Janar Kelly-Kenny, wanda ya kasance wani ɓangare na Ƙungiyar Ƙungiyar Afirka ta Kudu. Bayan Taimako na Kimberley, ya shiga cikin
Yaƙin Paardeberg a watan Fabrairun 1900, kuma ya ji rauni sosai ta hanyar harbi a kirji. A watan Maris na 1902, an nada shi zuwa umurnin Bloemfontein garrison a Orange River Colony. Bayan karshen yakin a watan Yuni na wannan shekarar, Knox ya koma Ingila a cikin "SS Dunottar Castle", wanda ya isa Southampton a watan Yulin 1902. Don ayyukansa a lokacin yaƙin, an ambace shi sau uku a cikin Wasiku, an ba shi lambar yabo ta Sarauniya ta Afirka ta Kudu da lambar yabo ta Afirka ta Kudu ta Sarki, an ba shi babban babban janar (wanda aka yi shi a ranar 4 ga Disamba, 1899), kuma an ba shi matsayin Knight Commander na Order of the Bath (KCB) a cikin Afrilu 1901 South Arica Honours list (an ba da umarnin a ranar 29 ga Nuwamba, 1900, kuma an saka shi ne kawai bayan dawowarsa gida, daga Sarki Edward VII a Fadar Buckingham a ranar 24 ga Oktoba, 1902).