Francis Drake then directed his course at once to the West Indies. He surprised St. Domingo and Carthagena, occupied both one and the other for a short time, and levied heavy contributions on them. Then he brought back to England the colonists from Virginia, who were not yet able to hold their own against the natives. The next year he inflicted still more damage on the Spaniards. He made his way into the harbour of Cadiz, which was full of vessels that had either come from both the Indies or were proceeding thither: he sank or burnt them all. His privateers covered the sea. Often already had the Spaniards planned an invasion of England. The most pressing motive of all lay in these maritime enterprises. The Spaniards remarked that the stability and power of their monarchy did not rest so much on the strong places they possessed in all parts of the world as on the moveable instruments of dominion by which the connexion with them was kept up; the interruption of the communication, caused by Francis Drake and his privateers, between just the most important points on the Spanish and the Netherlandish coasts, seemed to them unendurable: they desired to rid themselves of it at any price. And to this was now added the general cry of vengeance for the execution of the Queen of Scots, which was heard from the pulpit in the presence of the King himself. But this was not the only result of that event. The life of Queen Mary and her claim to the succession had always stood in the way of Spanish ambition: now Philip II could think of taking possession of the English throne himself. He concluded a treaty with Pope Sixtus V, under which he was to hold the crown of England as a fief of the Holy See, which would thus, and by the re-establishment of the Church's authority, have also attained to the revival of its old feudal supremacy over England.[267] Once more the Spanish monarchy and the Papacy were closely united in their spiritual and political claims. Sixtus V excommunicated the Queen afresh, declared her deposed, and not merely released her subjects from their oath of allegiance, but called on every man to aid the King of Spain and his general the Duke of Parma against her.