The Battle of Trafalgar (21 October 1805) was a naval engagement between the British Royal Navy and the combined fleets of the French and Spanish Navies during the War of the Third Coalition (August-December 1805) of the Napoleonic Wars (1803-1815). Drawing. As part of Napoleon's plans to invade England, the French and Spanish fleets combined to take control of the English Channel but they encountered the British fleet under Admiral Lord Nelson. The ensuing fierce battle resulted in 22 allied ships being lost, while the British lost none.