The religious aspect of Russian life has been dwelt upon at some length, because it is the key to everything in Russia and has a direct bearing upon the present war. "Religion in Russia," writes Mr. Maurice Baring, "is a part of patriotism. The Russian considers that a man who is not Orthodox is not a Russian. He divides humanity, roughly, into two categories--the Orthodox and the heathen--just as the Greeks divided humanity into Greeks and Barbarians. Not only is the Church of Russia a national church, owing to the large part which the State, the Emperor, and the civil authority play in it, but in Russia religion itself becomes a question of nationality, nationalism, and patriotism." Russian Christianity, like Russian Tsardom, is derived from the old Roman empire of Constantinople. The Russian Church is a branch, and far the most important branch, of the Greek Orthodox Church, which drifted apart from the Catholic Church, which had its centre at Rome, and finally separated from it in the eleventh century. As the greatest Orthodox Christian power in the world, Russia naturally regards herself as the rightful protector of all Orthodox Christians. Her mortal enemy, with whom so long as he remains in Europe any lasting peace is impossible, is the Turk; and her eyes are ever directed towards Constantinople, as the ancient capital of her faith. The spirit of the Crusades is far from dead in the Russian people; the Crimean War, for example, was fought in that spirit. It will be at once apparent that Russia takes and must continue to take a profound interest in the Christian peoples of the Balkans. Greeks, Roumanians, Servians, Bulgarians and Montenegrins all belong to the Orthodox Church; all have been engaged throughout the nineteenth century in a struggle for existence against the common foe, Islam. Moreover, all except the two first-mentioned peoples are allied to Russia by ties of race as well as by religion, since they are members of the Slavonic stock. To the average Russian, therefore, the bulk of the Balkan peninsula is as much Russia Irredenta, as the north-east coast of the Adriatic is Italia Irredenta to the average Italian; and as a matter of fact there is a good deal more to be said for Russia's case than for Italy's. There is, however, another great power which possesses interests in the Balkans and which is viewed by Russia with a suspicion and dislike hardly inferior to that entertained towards Turkey--I mean the empire of Austria-Hungary. A Catholic state, controlled by Germans and Magyars, Austria-Hungary contains in its southern portion a population of over seven million Slavs, some three millions of whom are of the Orthodox faith. The Dual Monarchy has constantly outraged national and religious feeling in Russia by her treatment of this Slavonic population, and her annexation in 1908 of Bosnia and Herzegovina, both of them Slavonic countries, was regarded as an open challenge to Russia.