The 10th Royals came into existence in 1861 under the Canadian Militia Act of 1855. It was a regiment of volunteer militia of working men from Toronto, and was led by Lieutenant-Colonel F.W. Cumberland. It served in the Fenian Raid of 1866, and after a number of variations in name was reorganized as the Royal Grenadiers in 1880. In 1881 it was renamed the 10th Battalion, Royal Grenadiers. It fought in the Riel Rebellion of 1885.