Thomas O'Hagan, 1st Baron O'Hagan

The Right Honourable The Lord O'Hagan KP PC QC
Lord O'Hagan, c. 1868.
Lord Chancellor of Ireland
In office 1868–1874
Monarch	Victoria
Prime Minister	William Ewart Gladstone
Preceded by	Abraham Brewster
Succeeded by	In commission
In office 1880–1881
Monarch	Victoria
Prime Minister	William Ewart Gladstone
Preceded by	John Thomas Ball
Succeeded by	Hugh Law
Personal details
Born	29 May 1812 (1812-05-29) Belfast
Died	1 February 1885 (1885-03) (aged 72) Hereford House, London
Nationality	British
Political party	Liberal

Thomas O'Hagan, 1st Baron O'Hagan, KP, PC (Ire), QC (29 May 1812 – 1 February 1885), was an Irish lawyer and judge. He served as Lord Chancellor of Ireland from 1868 to 1874 and again from 1880 to 1881.