29th July 1588; the Spanish armada was defeated by the English fleet led by Sir Francis Drake. In 1588 the most powerful, best-organised, best-equipped army in Europe - the Spanish 'Army of Flanders' - had almost crushed the Dutch revolt in the northern provinces of the Spanish Netherlands. Their commander, the respected and feared Duke of Parma was poised ready to embark his troops to cross the narrow end of the North Sea.

They would land in the Deal - Sandwich area. England's land defences were poor: troops were hastily recruited volunteers with little equipment or training; there were no modern fortifications, and Henry VIII's 50-year old coastal castles were already vulnerable to modern guns. It is likely that the battle-hardened Spanish troops with their powerful artillery would have swept through Kent overwhelming the opposition, and have captured London within a week.

It is fairly certain that Spanish king Philip II did not want or intend to rule England as part of the Spanish empire - or to make English people speak Spanish. As a zealous Catholic, his deepest wish was to return England to the "true church", to restore Church lands and property stolen by Henry VIII, reopen the monasteries, and restore Catholic forms of worship. The Pope had agreed to support an invasion. He excommunicated the English Queen Elizabeth, absolved her subjects from any duty to obey her, and offered financial help and papal blessing for an invasion. Philip, subject to the Pope's approval, would choose a new ruler pledged to restore the Catholic faith.

The new ruler might have been Mary Stuart, "Queen of Scots" - a Catholic brought up in France - but in 1587 Elizabeth had Mary beheaded, after she had been involved in a series of Catholic plots to assassinate Elizabeth. A victorious Philip would not impose many other conditions: he wanted English soldiers withdrawn from the Spanish Netherlands; especially the English garrison at Flushing which blockaded the recaptured key port of Antwerp - at this stage, English help was perhaps the only thing stopping the complete collapse of the revolt by the Protestant Dutch. Philip also wanted to stop the attacks of English "pirates" like Sir Francis Drake on Spanish treasure ships and trade in the Caribbean and round the world.

Immediately after a successful invasion, Cardinal William Allen, the English Cardinal-in-exile and head of the English College in Douai, would take over the temporary administration of England, and work with English Catholics to restore the Catholic Church. The plan did not depend on English Catholics rising up to revolt, though it was expected that they would eagerly cooperate once it succeeded. If the English were not decisively beaten, Philip's instructions were that Spanish negotiators should at least try to secure toleration of Catholics in England before retreating.

Philip gave instructions for a huge and extremely costly fleet of ships to be prepared, for two purposes: to hold the narrow seas between England and Flanders, so that the Duke of Parma's army could cross safe from attack by English or Dutch ships. And to carry additional soldiers plus supplies and siege artillery to wage war in England.

The one problem they never resolved was how to arrange a meeting between the Armada and Parma's Army? Both the soldiers and their barges were dispersed across Flanders to maintain some element of secrecy. They kept the Dutch rebels and the English guessing about their intentions - were they going to attack Holland or England? Parma reckoned it would take about 6 days to gather Army and barges together and set out to sea. Yet without radio or any speedy communications, it was impossible for the Armada to give advance warning of when it would actually be approaching the Flanders coast. If Parma's men had just waited in their boats off Dunkerque, they would have been "sitting ducks" for attack by Dutch fighting ships which were very effective in these shallow coastal waters.

France and Spain were rival Continental giants - each had huge population and taxable resources, the things that made kings powerful; each feared the other gaining too much power (the small off-shore island of England was a fraction of their size and fighting weight) So a Spanish Armada sailing up the Channel could seek shelter neither along the hostile south coast of England, nor in French ports, where in any case there were few harbours able to handle big ships.

At this time France was weakened by Wars of Religion. Although a Protestant King (Henri III) had inherited the throne, the Protestant minority (called "Huguenots") continued to be persecuted by powerful bishops and nobles, led by the Duc de Guise and the "Catholic League". The Catholic League nobles held strongholds in the east of France, and with financial support from Philip, set out to capture the fortified port of Boulogne, then close to the border with the Spanish Netherlands, from where the Catholics hoped to receive reinforcements. An English spy warned the royal garrison, who shut the gates and resisted; Elizabeth sent part of the navy across the Channel in support. She also sent German mercenaries across the Rhine to help the beleaguered Huguenots - so Guise could not spare enough troops to capture Boulogne. As a result, Philip failed to gain a safe port which might have made a crucial difference to the success of the Armada. However he paid Guise to arrange a big Catholic revolt timed to coincide with the passage of the Armada, to reduce France to chaos so that the Huguenots could not help their English allies.

In May 1588, Philip's fleet set sail from Lisbon with 130 ships and 19,000 men, commanded by Medina Sidonia carrying detailed instructions from Philip. While waiting for supplies off Corunna in northern Spain, the fleet was scattered by a storm. Disheartened, they did not restart their voyage until July, under direct orders from an angry Philip. Meanwhile the Duke of Guise and French Catholics took to the barricades in Paris as promised.

The English fleet under Admiral Lord Howard totalled 197 ships, of which 34 were in the Navy, and the rest were armed merchant ships. The Western Squadron set sail from Plymouth and attacked the Amada as it made its way eastwards. At first English commanders feared the "invincible" reputation of the Spanish galleons and kept their distance, just picking off stragglers. But they saw that Sidonia was heading for the Isle of Wight, to anchor in shelter until he received a reply from Parma confirming that the Army was ready and would meet him off Margate. Howard concentrated his navy into four groups. Their fiercer attack was enough to drive the Spanish away from the Isle of Wight - though it left the English woefully short of ammunition.

Sidonia decided to move the rendezvous closer to Parma, and meet him off Calais rather than Margate. The Governor of Calais (picture R) was a sympathetic Catholic, who allowed the Spanish to anchor off-shore by the guns of the town forts, and to buy fresh food, vegetables, and water. There he received his first reply from Parma, who had only just heard of the Armada's approach. It would be 6 days before the army would be ready to be escorted across the Channel. English and Dutch warships lay in wait off Dunkerque to attack Parma's vulnerable barges, but it was too risky for the Armada to approach closer than Calais - the Dutch had removed navigation markers and buoys from the treacherous sandbanks all along the Flemish coast. Meanwhile the Spanish fleet had to wait - crowded together, anchored in the strong tidal currents of the narrow seas close to Calais - waiting for Parma.

Admiral Howard called a council of war. To take advantage of the Spanish position, he sent for fire ships - old hulks stuffed with firewood, tar and loaded guns. At night, these were set ablaze and released to drift with the wind amongst the Spanish ships. The Spanish captains panicked - to avoid heavy losses, they cut their cables - losing their anchors on the seabed, and fled in confusion. With no anchors, it would be difficult for them to resume their wait by the coast.

On the following day, reinforced by the Eastern Squadron and with new supplies of ammunition, the enlarged English navy attacked the Armada for the first time. There was a pitched battle out in the North Sea between Gravelines and Ostend. The English used modern tactics, with a new role for ship-born guns. The Spanish followed the traditional tactic of firing guns once at close range, then boarding the enemy ship and fighting the crew with anti-personnel weapons that scattered fire and shrapnel. Their guns crews were not trained to reload and fire repeatedly, nor were their guns mounted in such a way to make this easy or even possible in battle. The Spanish galleons were ocean-going vessels designed with large cargo holds to carry supplies for a long voyage, plus equipment for land wars once they arrived - which made them slow and cumbersome.

The English navy, on the other hand, had fast manoeuvrable ships designed to defend their coastal waters. Their guns crews were trained in rapid reload and the cannons were mounted on small-wheel trucks which made this possible onboard ship. As a result, the English got in many more shots than the Spanish, and inflicted more damage without actually boarding the enemy ships. The battle raged for a day, and was not conclusive - but it convinced both the Spanish and the English that the Armada was not invincible. Sidonia did not realise that the English had again run out of ammunition, and believed that he had no chance of succeeding in his mission of gaining control of the sea between Flanders and England. Without telling Parma, he set sail northwards.

There was still great concern about the dangerous threat of a fleet of 100 enemy ships at large in the North Sea - and a professional army in Flanders which was still poised ready to invade. Would the Armada perhaps seek repairs and supplies in Denmark or Norway, then return to attack again? For several anxious weeks, the English navy and armies waited on full alert.... But eventually they found out - amid great Protestant rejoicing - that the Spanish fleet had set sail on what turned out to be a disastrous journey back home, up the east coast of England. As they went round the north of Scotland and Ireland in terrible gales most of their galleons were sunk.

Despite the legends that have come down through history, it was a very close thing. The news that the threat of invasion was over was a big boost to Protestant morale throughout Europe. Dutch rebels and French Huguenots saw that mighty Spain could be beaten, and that Philip did not always seem to have God on his side.

War between England and Spain dragged on until her successor, James I (son of Mary Queen of Scots) opened negotiations in 1604, and secured a peace treaty - which gave Spain most of the concessions for which they had sent the Armada in 1588. However, just a year later, the peace was shattered by the Gunpowder Plot.