The attack on Spain was to be conducted on three lines. One does not concern us, except in so far as it is necessary to remember that unless England had possessed a superiority of strength at sea, she could not have followed it. At a later period English troops were sent to co-operate in the conquest of the Spanish Netherlands. But before this, Spain had been attacked on the sea. Two expeditions were fitted out in England. The first, under the command of Robert Blake, was to sail for the Mediterranean, and, after disposing of certain preliminary duties, was to attack Spain at home. The second, under the combined commands of William Penn as general-at-sea, and of Robert Venables as general of the land forces, was to fall upon the Spaniards in the New World. This second expedition marks a notable epoch in our colonial history, and, at the cost of somewhat forestalling the order of time, may be told as an episode by itself.
According to all modern notions, the policy of Cromwell in fitting out this expedition was eminently immoral. A great fleet carrying a force of soldiers was sent out with orders to attack the Spaniards before a declaration of war. But in the middle of the seventeenth century, and in the circumstances, there was nothing even irregular in what the Protector did. It is necessary to understand in their main lines the relations of European States to Spain in the New World, and to do that we must look back for a moment. At the close of the fifteenth century, the almost simultaneous voyages of Columbus across the Atlantic and of Vasco da Gama round the Cape of Good Hope had appeared to give the Crowns of Spain and Portugal the rights of previous discovery over the trade routes to the East. It must not be forgotten that Columbus was believed to have reached the eastern extremity of Asia. He himself died in the belief that this was what he had done. It was not until Vasco Nuñez de Balboa had crossed the Isthmus of Darien, and Magellan had sailed through the straits named after him, and had found a vast expanse of ocean between him and Asia, that it came to be understood that there was a continent of America. In 1494 it was thought that Asia had been reached, and it appeared not improbable that Spain and Portugal would come to blows over the limits of what we should now call their respective spheres of influence. The two States appealed to the Pope, Alexander VI., and he drew a line between them running from pole to pole 100 miles to the west of the Cape de Verd Islands. The decision of the arbitrator did not appear satisfactory to the Portuguese, who would have been confined too closely to the coast of Africa. They protested, and their protest was listened to by the Catholic sovereigns, Isabel of Castile and Ferdinand of Aragon. In the year after the Pope had given his decision, a conference was held at the town of Tordesillas, and it was then settled that the line of demarcation should run 300 leagues to the west of the Azores and in the corresponding meridian on the other side of the globe. In the course of time, it was found that this decision had thrown by very much the greater part of the two American continents into the share of Spain. Other nations refused, indeed, to allow that the bull "Inter cætera" gave Spain any exclusive rights. But the Spanish Government was of another opinion. It abstained, indeed, from interfering with the English settlements in New England and the French in Canada, which were poor and distant. Its own weakness forced it so far to acquiesce in what it could not prevent, but it never recognised the legitimacy of foreign settlements; and whenever any of them approached those regions where the Spanish rule was strong, they were liable to attack, even when peace prevailed in Europe. The Spaniards, in fact, recognised no peace beyond the line--that is to say, the line of demarcation from north to south, and not, as is sometimes supposed, the equator.