Called by the Spaniards before it sailed the felicissima, most fortunate, and invencible, invincible. It was a great fleet assembled by King Philip II of Spain to force the English Channel, pick up the army of the Prince of Parma then operating in the Low Countries, and invade England. The fleet, consisting of 130 ships, both large and small, was commanded by the Duke of Medina Sidonia (1550–1619). It left Lisbon in May 1588 but made such poor headway because of heavy weather that it had to put in to Corunna for repairs, water, and provisions, and it was another month before it again set sail.
The English fleet, initially larger in number but much smaller in tonnage, was divided between Lord Howard of Effingham's squadron at Plymouth, and Lord Henry Seymour's ships at Dover, which was watching Calais for the arrival of Parma's army. The western squadron sailed from Plymouth as soon as the Armada was sighted off the Lizard on 19 July, an event which gave rise to the well-known legend of Sir Francis Drake and his game of bowls on Plymouth Hoe. The first shots of the battle were fired off the Eddystone on 21 July.
The Spanish fleet was sailing in a crescent-shaped formation, too strong for the English ships to attack in formation, but, being generally more weatherly, they attacked singly at long range, exploiting superior naval gunnery techniques and equipment to keep the Spanish ships on the move. During the next four days the Armada was continually harassed, losing two ships, and by the evening of the 25 July the two fleets were abreast the Isle of Wight. By this time the English ships were running short of ammunition and Howard, when reporting this, stated his intention not to attack again until he had obtained a further supply.
Meanwhile the Armada continued its slow progress up Channel, losing an occasional straggler to the English ships, but in general keeping its crescent-shaped formation intact. It anchored off Calais on the evening of 27 July to await Parma's troops for the planned invasion. As it dropped its anchors, so also did Howard's squadron, which was promptly reinforced by Seymour's ships.
With the wind blowing from the south-west, the English fleet now anchored about 800 metres (2,640 ft) to windward of the Spaniards, very well placed for an attack with fireships. Six of these were sent down on the following night, causing much consternation and confusion among the tightly packed Spaniards. There was nothing they could do but cut their cables and make sail before the wind to escape the threatened holocaust. They were followed by the whole English fleet and a major action developed off Gravelines, in which Medina Sidonia lost three of his best ships and found himself being driven by the wind and the English towards the Dutch shoals. At the last moment the wind backed into the south-east and enabled the Spanish ships to claw off the dangerous shallows.
Without Parma's troops on board, and with the invasion now impossible, Medina Sidonia had no option but to make his way back to Spain as best he could. Short of ammunition and provisions, he could not fight his way back down Channel through the English fleet, and the only way left for him was around the north of Scotland and west of Ireland. Leaving Seymour and his squadron to guard the Channel and maintain a watch for any movement by Parma and his troops, Howard pursued the retreating Armada up the North Sea as far as the latitude of the Firth of Forth. There, running short of supplies himself, he decided to abandon the chase, though a few English pinnaces continued to follow the Spaniards until they were past the Orkney Islands, and committed to returning to Spain by the west of Ireland. The weather, which had been rough in the North Sea, deteriorated further as the Armada ploughed its long way homewards, and many of its vessels were wrecked on the rocky coasts of Scotland and Ireland, where they were pillaged and their crews slaughtered. Of the 130 Spanish ships which had left Lisbon, almost half were lost.