Why did Philip II of Spain decide to invade England?

There were many important reasons why Philip II of Spain decided to invade England through the Spanish Armada, with the execution of Mary Queen of Scots spurring him to invade, the execution regarded by him as judicial murder.

            Firstly, Philip wanted to claim the English throne as widower of Mary Tudor, and also, Mary Queen of Scots had left it in her will that her claim to the English throne would be Philips.

            As mentioned above, Philip would have invaded earlier if it wasn’t for the fact that he would have been a threat to Mary’s life. But with the execution of Mary Queen of Scots, there was now nothing to stop him from invasion, coupled with outrage at the execution.

            In addition, the singeing of the King of Spain’s Beard caused the Spanish Armada. Drake’s attack on the Spanish galleons at Cadiz and the destruction of the barrel staves on the coast put back the Amada by a year, and this was a pre-emptive attack. 

            The Spanish Armada was also fought because of the activities of English privateers – real pirates plundering Spanish treasure ships on the Spanish Main. This annoyed Philip greatly, and, although Elizabeth in public tried to distance herself from these attacks, in private she supported them and Philip knew this, and this was yet another fact that brought Philip to invade England.

            Also, Philip invaded because the English had helped the Dutch in their attempt to free themselves from the Spanish Yoke. It was an English force sent under Leicester – the Battle of Zutphen, and as you can see this must have angered Philip very much.

            In conclusion, there were many factors due to Philip’s invasion which actually failed at the end, and Philip posed as a Catholic champion, the Pope’s avenging angel, against the heretic and murderous Queen.