The Battle of Lagos was fought during the Nine Years' War on 27 June 1693 (17 June 1693 O.S.), when a French fleet under Anne Hilarion de Tourville defeated an Anglo-Dutch fleet under George Rooke near Lagos Bay in Portugal. Rooke's squadron was protecting the Smyrna convoy, and it is by this name that the action is sometimes known.

In the spring of 1693, a large convoy was organized to transport English and Dutch merchant ships which were bound for Spain and the Mediterranean; they had been held back by the threat of attack by the French fleet, or by commerce raiders.

The convoy, consisting of upwards of 200 sail, was to be escorted by a strong squadron of eight English and five Dutch ships of the line, with fireships, scouts and other auxiliaries, under the command of Vice-Admiral George Rooke and Rear Admiral Philips van der Goes. This squadron was bound for the Mediterranean, to take up station there. The convoy was to be covered by the combined allied fleet for its passage across the Channel, until it was past the port of Brest, to guard against attack by the French stationed there. The fleet, which was also charged with protecting England from the threat of invasion, would then double back to cover the Channel.

The French, however, whilst they had made good their losses of the previous year, had abandoned the intent to invade in favour of a guerre de course, a war against the allies' trade and commercial interests.

To this end, Louis XIV had dispatched the French fleet under Tourville, his most able commander, to set an ambush for the convoy before it entered the Straits of Gibraltar. By the end of May, Tourville had assembled a fleet of 70 ships of the line, plus fireships, stores vessels and other auxiliaries, about 100 sail in total; and taken up station near Lagos Bay in Portugal.

The convoy sailed at the end of May, with the allied fleet of 24 Dutch warships under Philips van Almonde and 45 English under a leadership committee of Admirals Henry Killigrew, Ralph Delaval and Cloudesley Shovell.

By 7 June (O.S) the convoy was about 150 miles southwest of Ushant, and the main allied fleet had turned back, leaving Rooke and the convoy to proceed south. The allies had made no move to check where the French fleet was, and received no news of its whereabouts until 17 June (O.S). By this time Rooke and the convoy were in action off Lagos, having been sighted by the French on the morning of 17 June (O.S).

Rooke could not avoid battle, but held the advantage of being to windward. Ordering the merchant ships to disperse, his squadron took up battle positions. The battle started around 8 pm. when the rear of his squadron was overtaken by the French van, led by Jean Gabaret [fr]. Two Dutch ships, Zeeland (64, Philip Schrijver) and Wapen van Medemblik (64, Jan van der Poel), engaged the French, thus sacrificing themselves. They fought valiantly, giving the rest of the allied ships time enough to escape. When the two Dutch ships finally surrendered, Tourville was very impressed and congratulated the two captains, asking them if they "were men or devils".
Rooke declared it "one of the best judged things I ever saw in action".