Battle of Waterloo
The battle of Waterloo took place in the Belgian province of Waterloo. It saw the defeat of Napoléon Bonaparte at the hands of the Duke of Wellington.
This defeat marked the beginning of the end for the French empire. In reference to this, the Fourth Doctor related the defeated of the Sontarans as "their Waterloo". (DW: The Sontaran Experiment)
While teaching at Farringham School for Boys, John Smith gave a lesson on Napoléon's defeat at Waterloo. (DW: Human Nature)
In a history project for school, Clyde Langer and Luke Smith were required to show the battle stratagies by Wellington and Napoleon at the battle. The pair re-enacted the battle on Mr Smith. (SJA: The Last Sontaran)
After the battle, Wellington told the Fourth Doctor, "'The only thing sadder than a battle lost, is a battle won." Some time later, the Doctor considered how right he was. (EDA: The Eight Doctors)