Which battle in 1805 ensured British naval supremacy for a century?

Which battle in 1805 ensured British naval supremacy for a century? The answer is the Battle of Trafalgar. Fought on 21 October 1805 off Spain’s Cape Trafalgar, it pitted 27 British ships of the line under Vice-Admiral Horatio Nelson against a combined French and Spanish fleet of 33 ships of the line.

Nelson divided his fleet into two columns and attacked the enemy line directly, breaking it into isolated sections. The tactic exposed British ships to heavy fire but disrupted the allied fleet’s formation. Britain captured or destroyed 18 enemy ships without losing a ship of the line, though Nelson was mortally wounded and died during the battle.

Trafalgar ended Napoleon’s practical hopes of invading Britain by sea and confirmed the Royal Navy’s dominance. The phrase “for a century” is a useful shorthand rather than an exact legal period: Britain’s naval superiority rested on wider economic and industrial strength as well as this victory. The Royal Navy was not meaningfully challenged in a comparable fleet action until World War I.