The Spanish Armada was a fleet assembled and dispatched by King Phillip II of Spain in attempt to invade England in 1588. His attempt was unsuccessful. Queen Elizabeth I of England held the defeat of the armada as one of her greatest achievements, assisting the decline of the Spanish Empire. The armada had a mission of both political and religious aims. King Phillip, the leader of the Roman Catholic Spain, was not able to stop a revolt in of his Protestant subjects the Netherlands, a revolt which began in 1566, aided by Protestant England.