Here it is: "Heart of Oak."
It was written to celebrate the victories of 1759 over the French and their allies in the Seven Years War and French and Indian War, but more specifically the Battle of Quiberon Bay.
Interestingly, the lyrics were composed by that famous actor David Garrick, who appears in a couple of posts on this blog as the "Drunken Sailor."
"Heart of Oak" was wildly popular, and sung throughout the empire. Today it is still the official march of the Royal Navy.