The French third rate two-decker L'Aigle was laid down at Rochefort in 1798 and launched in 1800. Mounting 74 guns in all, principally 28-36pdrs. on her lower deck supported by 30-24pdrs. on her upper deck, she carried a crew of 755 officers and men, including marines, and began her career under the command of Captain Hubert. By March 1805 she was lying in Cadiz, from where she joined Villeneuve's combined fleet for the feigned expedition to the West Indies which was intended to lure Nelson across the North Atlantic and strand him there whilst the Franco-Spanish fleet doubled back to attend to the invasion of England. After accompanying this foray and then taking part in the inconclusive action against Sir Robert Calder's squadron off Cape Finisterre on 22nd July [1805], she then found herself with a new commander, Captain Pierre Gourrège, when Captain Hubert transferred to L'Indomptable, and it was Gourrège who took her into battle on 21st October.

At Trafalgar, L'Aigle was part of the 'squadron of observation' at the rear of the combined fleet and fired her first shots at H.M.S. Bellerophon just before the two ships collided and became locked together. Despite the fact that Bellerophon was being attacked by four enemy vessels, she nevertheless concentrated her starboard broadside onto L'Aigle lying only feet away. On the upper decks and in the fighting tops, a furious exchange of musket-fire left both Captain Gourrège and Captain Cooke (of Bellerophon) fatally wounded yet, despite the damage done by Bellerophon's murderous broadsides, L'Aigle fought on magnificently and managed to break clear to engage H.M.S. Revenge. Still undefeated, it was only the untimely arrival of H.M.S. Defiance to join the action that finally forced L'Aigle to strike her colours at about 3 o'clock. The cost of her prolonged resistance had been high, with some 270 men killed or wounded, and many more were to follow them when, five days later on 26th October, L'Aigle was one of the numerous prizes which were lost during the great storm which decimated the fleets in the aftermath of battle.