The Battle of Trafalgar (21 October 1805) was the most significant naval engagement of the Napoleonic Wars and the pivotal naval battle of the 19th century.

The British Royal Navy led by Horatio Nelson destroyed a combined French and Spanish fleet and in so doing guaranteed to the United Kingdom uncontested control of the world's oceans for more than 100 years. Because the British won the Battle of Trafalgar, they, not the French, would rule an expanded empire that included India, Canada, Hong Kong, Singapore, around the world and a world economy with London, not Paris, as the pre-eminent financial seat of Europe.

In 1805 under Napoleon, the French were masters of the European continent, while the British still ruled the seas. The British, during the course of the war, managed to impose a fairly effective blockade on France. This blockade had the effect of keeping the French from fully mobilizing their own naval resources and kept the French from invading Britain although Britain could always land in France.

Disgusted with this situation, Napoleon Bonaparte determined to sweep the Royal Navy from the seas, and issued orders for the French Navy to combine with forces from the Spanish Navy (Napoleon ruled Spain), break the British blockade, then escort an invasion force of some 350,000 French soldiers to the shores of England.

Napoleon had had his troubles with the Royal Navy before. The French occupation of Egypt was ultimately undone when Nelson smashed the French fleet in the Battle of the Nile off Alexandria. Were this all Nelson had done, he would be still be regarded as a famous admiral, but his greatest day was yet to come.

Source : Wikipedia, the free encyclopedia.