Alexis had a war with the Poles that proved successful, and terminated in a peace, which secured to him the possession of Smolensko, Kiow, and the Ukraine: but he was unfortunate against the Swedes, and the boundaries of the Russian empire were contracted within a very narrow compass on that side of the kingdom. The Turks were at that time his most formidable enemies: they invaded Poland, and threatened the dominions of the czar that bordered upon Crim Tartary, the ancient Taurica Chersonesus. In 1671, they took the important city of Kaminiek, and all that belonged to Poland in the Ukraine. The Cossacks of that country, ever averse to subjection, knew not whether they belonged to the Turks, Poland, or Russia. Sultan Mahomet IV. who had conquered the Poles, and had just imposed a tribute upon them, demanded, with all the haughtiness of an Ottoman victor, that the czar should evacuate his possessions in the Ukraine, but received as haughty a denial from that prince. Men did not know at that time how to disguise their pride, by an outside of civility. The sultan, in his letter, styled the sovereign of the Russias only Christian Hospodar, and entitled himself 'most gracious majesty, king of the universe.' The czar replied in these terms, 'that he scorned to submit to a Mahometan dog, and that his scimetar was as good as the grand seignior's sabre.' Alexis at that time formed a design which seemed to presage the influence which the Russian empire would one day obtain in the Christian world. He sent ambassadors to the pope, and to almost all the great sovereigns in Europe, excepting France (which was in alliance with the Turks), in order to establish a league against the Ottoman Porte. His ambassadors at the court of Rome succeeded only in not being obliged to kiss the pope's toe; and in other courts they met with only unprofitable good wishes; the quarrels of the Christian princes between themselves, and the jarring interests arising from those quarrels, having constantly prevented them from uniting against the common enemy of Christianity.