From the time of Drake's voyage round the world (1577) and its insulting defiance of the Spanish power on the west coast of South America, it became plain that the maintenance of Spanish monopoly could not last much longer. It came to its end, finally and unmistakably, in the defeat of the Grand Armada. That supreme victory threw the ocean roads of trade open, not to the English only, but to the sailors of all nations. In its first great triumph the English navy had established the Freedom of the Seas, of which it has ever since been the chief defender. Since 1588 no power has dreamt of claiming the exclusive right of traversing any of the open seas of the world, as until that date Spain and Portugal had claimed the exclusive right of using the South Atlantic, the Pacific, and the Indian Oceans. So ends the first period in the imperial expansion of the Western peoples, the period of Spanish and Portuguese monopoly. Meanwhile, unnoticed in the West, a remarkable eastward expansion was being effected by the Russian people. By insensible stages they had passed the unreal barrier between Europe and Asia, and spread themselves thinly over the vast spaces of Siberia, subduing and assimilating the few and scattered tribes whom they met; by the end of the seventeenth century they had already reached the Pacific Ocean. It was a conquest marked by no great struggles or victories, an insensible permeation of half a continent. This process was made the easier for the Russians, because in their own stock were blended elements of the Mongol race which they found scattered over Siberia: they were only reversing the process which Genghis Khan had so easily accomplished in the thirteenth century. And as the Russians had scarcely yet begun to be affected by Western civilisation, there was no great cleavage or contrast between them and their new subjects, and the process of assimilation took place easily. But the settlement of Siberia was very gradual. At the beginning of the eighteenth century the total population of this vast area amounted to not more than 300,000 souls, and it was not until the nineteenth century that there was any rapid increase. III THE RIVALRY OF THE DUTCH, THE FRENCH AND THE ENGLISH, 1588-1763