 Nyora kupfuurira kweiyi ndima - Roberts, akasimudzirwa kuva lieutenant musi wa3 Gunyana 1914, pamwe nebato rake, raitungamirirwa naLieutenant Colonel George Grogan, vakadzokera kuUnited Kingdom nguva pfupi mushure mekuziviswa kwehondo uye vakasvika ikoko muna Gumiguru 1914, kwavakava chikamu che24th Brigade ye8th Division, iyo yaive panguva iyoyo iri mukugadzirwa. Bhatani racho rakatumirwa kunosimbisa British Expeditionary Force BEF kuWestern Front uye rakasvika muFrance muna November 1914. Bhatani racho rakabatanidzwa mumabasa echando 19141915 uye rakabatanidzwa muKisimusi truce. Mwedzi mitatu asvika, Roberts akapiwa Distinguished Service Order achitungamirira kurwisa kwaaiita. Akaitwa mubatsiri webato rake uye akarwa muHondo yeNeuve Chapelle, uye akasimudzirwa kuva kaputeni musi wa6 Nyamavhuvhu 1915 Akaramba ari adjutant kusvika muna Gumiguru 1916 paakaitwa brigade major we8th Divisions 23rd Brigade. Muchiitiko ichi, panguva yeHondo yePasschendaele inozivikanwawo seHondo yechitatu yeYpres muna Nyamavhuvhu 1917, Roberts akapihwa Military Cross MC. Musi wa24 Gumiguru 1917 akadzokera ku1st Battalion, Worcesters uye, aine makore makumi maviri nematanhatu chete, akasimudzirwa kuita chinzvimbo che lieutenant-colonel, uye akapiwa temporary command yebattalion, achiva mumwe wevadiki veBritish Army battalion commanders. 