The Anglo-Spanish War ( 1585 - 1604 ) was a conflict between the kingdoms of England , ruled by Elizabeth I of England , and Spain , where Philip II reigned. The reasons that led Philip II to the war were economic, political and religious: In the politically aspect, the growing power of the Spanish Monarchy (which in 1580 had annexed the Portuguese dominions , was constantly expanding in America , and had the support of the Habsburgs in Germany and the Italian princes) was considered by England a threat to its security. In the religious aspect the disagreements between both countries came from the times of Enrique VIII of England . The Protestant English was facing the Catholic Spanish. In the economic aspect, the constant expeditions of the English corsairs against the Spanish territories in the Indies and against the treasure fleet , which loaded with riches fed the finances of the metropolis, supposed for Spain a threat to their economic interests.