Admiral Viscount Lord Nelson and Vice Admiral Collingwood commanded the British Royal Navy, arrayed in a blockade across the English Channel. The Franco-Spanish fleet was commanded by Admirals d'Aliva and Cisternas of Spain, under the ultimate authority of Admiral Villeneuve of France. France and Spain lost 14,000 men during the battle, 10 times British casualties. A French sharpshooter killed Lord Nelson during the last stage of the battle. Villeneuve, shamed by his defeat, returned to France and committed suicide with a dagger.
The British fleet consisted of 25 ships of the line, four frigates and assorted smaller craft. Nelson's flagship, the HMS Victory, carried 104 cannon loaded with 24-pound iron balls. Two other British battleships, the Royal Sovereign under Admiral Collingwood and the Britannia, each carried 100 cannons. In total, the British fleet contained eight three-decker ships that each carried 90 guns or more.
Villeneuve's French fleet contained seven frigates and 33 ships of the line. Small detachments of riflemen were posted throughout the fleet. The flagship Bucentaure, Formidable and Indomptable all carried 80 cannons. French Commander Laurent Le Tourneur sailed as acting captain on the 90-gun Spanish Algesiras.
The Spanish fleet contained the largest ships of the engagement. The massive Santisima Trinidad, captained by Rear Admiral Cisneros, carried 136 guns. The Santa Ana and Principe de Asturias both carried 112 cannons. The 74-gun Redoubtable, under Captain Jean-Jacques Lucas, carried the sharpshooter that killed Lord Nelson.