Yet if the Netherlands escaped the direct control of Philip, their wealth might be appropriated at its source. The Portuguese were still intrenched in the East, and Dutch prosperity was in no small part founded on privileges granted at Lisbon. Philip's opportunity came in 1580 when a disputed succession to the throne opened the way to intervention and the rapid conquest of Portugal. At a stroke the Portuguese dominions in Africa and the East Indies were added to Spain's American possessions. Throughout Europe Philip was thought to have played a winning card; for the most desired sources of the world's wealth were at the disposal of the Catholic king if he could but police the sea. But so complete a monopoly was not to be endured by his rivals; and France, Holland, and England, as a necessary prelude to their colonizing activities in the New World and in the Old, gathered their forces to dispute the maritime supremacy of Spain. II It was well understood that the power of Philip II depended upon his American treasure, and his treasure upon his control of the sea. "The Emperor can carry on war against me only by means of the riches which he draws from the West Indies," cried Francis I when Verrazano brought home some treasure taken from Spanish ships in Western waters. And Francis Bacon expressed the belief of the age when he wrote that "money is the principal part of the greatness of Spain; for by that they maintain their veteran army. But in this part, of all others, is most to be considered the ticklish and brittle state of the greatness of Spain. Their greatness consisteth in their treasure, their treasure in the Indies, and their Indies (if it be well weighed) are indeed but an accession to such as are masters of the sea."