He was born in York (Toronto) in 1821, the son of Sir John Robinson, an important political figure in Upper Canada. He attended Upper Canada College. During the Upper Canada Rebellion of 1837, Robinson served as aide-de-camp to Sir Francis Bond Head. He later studied law and was called to the bar in 1844. He became an alderman in Toronto during the 1850s, including a term as mayor. He was elected to the 6th Parliament of the Province of Canada representing Toronto in 1858. He helped promote the Northern Railway and served as president from 1862 to 1875. He represented Algoma in the Canadian House of Commons in 1872 and represented West Toronto in 1878.