An Ontario Liberal Party politician, he held office from 1871-1872 as Second Premier of Ontario. Later in his career, he served in Canadian Prime Minister Alexander Mackenzie's cabinet.
After studying law at Upper Canada College, he established a Toronto law practice with his brother and fellow attorney, Samuel Hume Blake.
From 1892-1907, he left Canadian politics and entered the United Kingdom political arena, representing the Irish South Longford constituency in the British House of Commons.
His father, William Hume Blake, also had a career as a politician, and his grandson, H. H. Wrong, was a Canadian diplomat who served as Ambassador to the United States. Following their 1856 wedding, Blake and his wife Margaret raised seven children.
He and fellow Canadian politician Bill Davis both held office as Premier of Ontario.