The part she had played in the Napoleonic Wars, and in the events which followed them, had brought her more fully into contact with Europe than she had ever been before. The acquisition of Poland and Finland, which she obtained by the treaties of 1815, had increased this contact, for both of these states were much influenced by Western ideas. Russia had promised that their distinct national existence, and their national institutions, should be preserved; and this seemed to suggest that the Russian Empire might develop into a partnership of nations of varying types, not altogether unlike the form into which the British Empire was developing. But this conception had no attraction for the Russian mind, or at any rate for the Russian government; and the reactionary or pure-Russian school, which strove to exclude all alien influences, was inevitably hostile to it. Hence the period of reaction, and of eastward conquest, saw also the denial of the promises made in 1815. Poland preserved her distinct national organisation, in any full degree, only for fifteen years; even in the faintest degree, it was preserved for less than fifty years. Finland was allowed a longer grace, but only, perhaps, because she was isolated and had but a small population: her turn for 'Russification' was to come in due course. The exclusion of Western influence, the segregation of Russia from the rest of the world, and the repudiation of liberty and of varieties of type thus form the main features of the reactionary periods which filled the greater part of this age; and the activity of Russia in eastward expansion was in part intended to forward this policy, by diverting the attention of the Russian people from the west towards the east, and by substituting the pride of dominion for the desire for liberty. Hence imperialism came to be identified, for the Russian people, with the denial of liberty. But it is a very striking fact that each of the three main lines of territorial advance followed by Russia in Asia during this period led her to overstep the natural barriers which had made her an isolated and self-dependent empire, brought her into relation with other civilisations, and compelled her to play her part as one of the factors in world-politics. Russia had begun the conquest of the wild Caucasus region as early as 1802; after a long series of wars, she completed it by the acquisition of the region of Kars in 1878. The mastery of the Caucasus brought her into immediate relation with the Armenian province of the Turkish Empire, which she henceforward threatened from the east as well as from the west. It brought her into contact also with the Persian Empire, over whose policy, from 1835 onwards, she wielded a growing influence, to the perturbation of Britain. And besides bringing her into far closer relations with the two greatest Mahomedan powers, it gave her a considerable number of Mahomedan subjects, since some of the Caucasus tribes belonged to that faith.