Turkey, in a religious point of view, was the certain and inflexible enemy of Russia,--so handed down in all the traditions and teachings of centuries. To erect again on the lofty dome of St. Sophia the cross, which had been torn down by Mohammedan infidels, was probably one of the strongest desires of the Russian nation; and this desire was shared in a still stronger degree by all the Russian monarchs from the time of Peter the Great, most of whom were zealous defenders of what they called the Orthodox faith. They remind us of the kings of the Middle Ages in the interest they took in ecclesiastical affairs, in their gorgeous religious ceremonials, and in their magnificent churches, which it was their pride to build. Alexander I. was, in his way, one of the most religious monarchs who ever swayed a sceptre,--more like an ancient Jewish king than a modern political sovereign. But there was another powerful reason why the Russian czars cast their wistful glance on the old capital of the Greek emperors, and resolved sooner or later to add it to their dominions, already stretching far into the east,--and this was to get possession of the countries which bordered on the Black Sea, in order to have access to the Mediterranean. They wanted a port for the southern provinces of their empire,--St. Petersburg was not sufficient, since the Neva was frozen in the winter,--but Poland (a powerful kingdom in the seventeenth century) stood in their way; and beyond Poland were the Ukraine Cossacks and the Tartars of the Crimea. These nations it was necessary to conquer before the Muscovite banners could float on the strongholds which controlled the Euxine. It was not until after a long succession of wars that Peter the Great succeeded, by the capture of Azof, in gaining a temporary footing on the Euxine,--lost by the battle of Pruth, when the Russians were surrounded by the Turks. The reconquest of Azof was left to Peter's successors; but the Cossacks and Tartars barred the way to the Euxine and to Constantinople. It was not until the time of Catherine II. that the Russian armies succeeded in gaining a firm footing on the Euxine by the conquest of the Crimea, which then belonged to Turkey, and was called Crim Tartary. The treaties of 1774 and 1792 gave to the Russians the privilege of navigating the Black Sea, and indirectly placed under the protectorate of Russia the territories of Moldavia and Wallachia,--provinces of Turkey, called the Danubian principalities, whose inhabitants were chiefly of the Greek faith.