He joined the British military at the age of 17 and quickly rose to the rank of brigadier general after leading a series of successful military campaigns as a junior officer. He also served as Governor of Jamaica from 1756 until his death on 26 July 1759 at the age of 37.
Brigadier-General George Haldane fought in the Battle of Fontenoy in 1743, where he was wounded. He fought in the Battle of Dettingen in 1743 and he also fought in the 1745 Uprising against the Jacobites. He gained the rank of brigadier general in the service of the 3rd Guards, and fought in the Battle of Leffelt in 1747. His final service was in the Battle of Roucoux in 1747. After resigning his military command, Haldane held the office of Member of Parliament (M.P.) for Stirling Burghs between 1747 and 1756.
In 1756, at the age of 34, he was appointed to the office of Governor of Jamaica. He was welcomed to the island in a poem, "An Ode to George Haldane," by Francis Williams, who went on to become one of Jamaica’s most famous early writers and scholars.
- Sedgwick, Romney R. (1970). R. Sedgwick, ed. HALDANE, Patrick (c.1683–1769), of Bearcrofts, Stirling. The History of Parliament: the House of Commons 1715–1754. Boydell and Brewer. Retrieved 26 December 2015.
-  Historical reference
- http://thepeerage.com/p31118.htm Military service
- https://archive.org/stream/cu31924020417527/cu31924020417527_djvu.txt Appointment as Governor of Jamaica
- http://www.math.buffalo.edu/mad/special/Williams_Francis1700-70.html William Francis Eulogy
|Parliament of Great Britain|
James Erskine, Lord Grange
| Member of Parliament for Stirling Burghs
| Governor of Jamaica