The Spanish Armada was a naval force sent by Philip II of Spain in May 1588 to join up with a Spanish army coming from the Netherlands and invade Protestant England – the end goal being to overthrow Queen Elizabeth I and reinstate Catholicism.

The Armada failed to join up with the Spanish army, however – let alone successfully invade England – and the engagement has become a defining part of the mythology of Elizabeth and her reign. Here are 10 facts about the Armada.

1. It all started with Henry VIII and Anne Boleyn

If Henry hadn’t wanted to divorce Catherine of Aragon and marry Anne Boleyn then it’s unlikely the Spanish Armada would ever have come about. The Tudor king’s desire for divorce was the spark for the Reformation, which saw the country move from Catholicism to Protestantism.

Spain’s Philip was the widower of Catherine’s daughter and Elizabeth’s half-sister and predecessor, Mary I of England. Philip, a Catholic, saw Elizabeth as an illegitimate ruler because Henry and Catherine had never officially divorced under Roman law. He is alleged to have plotted to overthrow Elizabeth and install her Catholic cousin Mary, Queen of Scots, in her place.

Whether this was true or not, Elizabeth retaliated by supporting a Dutch revolt against Spain and funding attacks on Spanish ships.

2. It was the largest engagement of the undeclared Anglo-Spanish War

Though neither country officially declared war, this intermittent conflict between England and Spain began in 1585 with the former’s expedition to the Netherlands to support the Dutch revolt and continued for nearly two decades.

3. It had taken Spain more than two years to plan

Spain was the global superpower of the day in 1586, the year that Spain began making preparations to invade England. But Philip knew an invasion would nonetheless be extremely difficult – not least because of the strength of the English naval fleet which he had helped to build up while his deceased wife, Mary, had been on the English throne. And he wasn’t nicknamed “Philip the Prudent” for nothing.

These factors, combined with an English raid that destroyed 30 Spanish ships at the port of Cadiz in April 1587, meant that it would be more than two years before the Armada would set sail for England.

4. Philip’s campaign was supported by the pope

Sixtus V saw the invasion of Protestant England as a crusade and allowed Philip to collect crusade taxes to fund the expedition.

5. England’s fleet was much bigger than Spain’s

The Armada was made up of 130 ships, while England had 200 in its fleet.

6. But England was seriously outgunned

The real threat came from Spain’s firepower, which was 50 per cent more than England’s.

7. The Armada caught a group of English ships by surprise

A fleet of 66 English ships were re-supplying in the port of Plymouth, on England’s southern coast, when the Armada appeared. But the Spanish decided not to attack it, instead sailing east towards the Isle of Wight.

The English gave chase to the Armada, up the English Channel, and a lot of ammunition was spent. Despite this, the Spanish fleet maintained its formation well.

8. Spain then made the fatal decision to anchor in open seas off Calais

This unexpected decision taken by the Spanish admiral, the Duke of Medina Sidonia, left the Armada open to an attack by English ships.

In the clash that ensued, known as the Battle of Gravelines, the Spanish fleet was dispersed. The Armada was able to regroup in the North Sea but strong south-westerly winds prevented it from returning to the Channel and English ships then chased it up the east coast of England.

This left the Spanish ships with no alternative but to journey home via the top of Scotland and down past the west coast of Ireland – a risky route.

9. The English fleet didn’t actually sink or capture many Spanish ships

The Armada returned home with only around two-thirds of its ships. Spain lost around five of its ships in the Battle of Gravelines, but a far greater number were wrecked on the coasts of Scotland and Ireland during severe storms.

There was some disappointment over this in England, but Elizabeth was ultimately able to work the victory in her favour. This was in large part due to her public appearance with troops in Tilbury, Essex, once the main danger was over. During this appearance, she made a speech in which she uttered the now famous lines:

“I know I have the body of a weak, feeble woman; but I have the heart and stomach of a king, and of a king of England too.”

10. England responded with a “counter-Armada” the following year

This campaign, which was similar in scale to the Spanish Armada, is little talked about in Britain – no doubt because it proved a failure. England was forced to withdraw with heavy losses and the engagement marked a turning point in Philip’s fortunes as a naval power.

The military expedition is also known as the “English Armada” and the “Drake-Norris Expedition”, a nod to Francis Drake and John Norris who led the campaign as admiral and general respectively.