Whakaotihia te rerenga e whai ake nei: Ko Grasett te tuatoru o nga tama a Reverend Henry James Grasett, te Rector o St. James Cathedral i Toronto, me Sarah Maria Stewart. I whakaakona ia i tetahi kura motuhake o Toronto me Leamington College for Boys i Ingarangi. I te 19 o ona tau, ka hoki ia ki Kanata, a, ka uru atu ki nga hoia o Kanata. I whawhai ia ki te Niagara Peninsula i te wā o te
Fenian raid of 1866 with the 2nd Battalion, Volunteer Militia Rifles of Toronto, I te tau 1867, i uru atu ia ki te ope taua o Ingarangi e mahi ana ki te Royal Canadian Regiment i Kanata me Ingarangi ka eke ki te taumata o te rangatira i te wa i reti ai ia ki Toronto i te tau 1875, i reira ia i noho hei hoa i roto i te umanga kaipuke me nga kaihokohoko komihana. I te tau 1885, i whakawhiwhia ki a ia te taumata o te koroneela i roto i te pirihimana, a, i whakahaua ia ki te 10 o nga Royal Grenadiers Battalion i whawhai i roto i nga pakanga maha i te wa o te North-West Rebellion o 1885.