Lieutenant-Colonel Sir Terence O'Brien KCMG
Governor of Newfoundland
In office 1889–1895
Monarch	Queen Victoria
Personal details
Born	John Terence Nicholls O'Brien 23 April 1830 Manchester, Lancashire, England
Died	25 February 1903(1903-02-25) (aged 72) London, England
Military service
Allegiance	United Kingdom
Branch/service	British Army
Rank	Lieutenant-Colonel

Lieutenant-Colonel Sir John Terence Nicolls O'Brien KCMG (23 April 1830 – 25 February 1903^[1]) was a surveyor, engineer and colonial governor.

Born in Manchester, England, son of Major-General Terence O'Brien (died 1865), later General Officer Commanding, Ceylon, and acting Governor of Ceylon, O'Brien studied at Elizabeth College, Guernsey, and then attended the Royal Military College, Sandhurst and was commissioned into the 67th Foot, later transferring to the 70th Foot.

He served in the Indian Mutiny War. In 1881, he was appointed governor of Heligoland, knighted in 1887 and became governor of Newfoundland in 1889.

O'Brien as governor of Newfoundland helped precipitate the 1894 bank crash by his many dispatches to London noting that Newfoundland politicians under Premier William Whiteway's Liberal Government were uniquely corrupt and incompetent. He resigned from office in 1895 and returned to London.

The Newfoundland community of Terenceville was so named in his honour. O'Brien's son, Sir Charles O'Brien, also became a colonial governor.

O'Brien died in 1903 in London, England.

• Governors of Newfoundland
• List of people from Newfoundland and Labrador

• Biography at Government House The Governorship of Newfoundland and Labrador
• Biography at the Dictionary of Canadian Biography Online