Kammala jumla mai zuwa: An haifi Grant a Nairn a Highlands na Scotland, inda mahaifinsa ya kasance ministan Ikklesiya, kuma ya yi karatu a Nairn Academy, Aberdeen Grammar School da Marischal College, Aberdeen. A shekara ta 1846 ya shiga rundunar sojojin Indiya. Ya ga aikin aiki a cikin
Sikh War (1848<unk>49), ya yi aiki a duk lokacin Tawayen Indiya na 1857, kuma ya ji rauni a cikin ayyukan don taimakon Lucknow.