Iaroslaf left two sons, Andrew, who succeeded him in Souzdal, and Alexander who was duke at Novgorod. This younger son was an able as well as a brave man. On one occasion, when the Scandinavians had invaded Novgorod's territory aided by the Catholic Orders, Alexander had gained a great victory on the Neva, from which he is known in history as Alexander Nevski (1240). Upon his return to Novgorod he had a dispute with the vetche, and he left the city. After his departure the territory of the Republic was invaded by the German Sword-bearers who erected a fort on the Neva, captured Pskof, Novgorod's ally, and plundered merchants within a short distance of the walls. The people sent to Alexander Nevski, begging him to come to their rescue, and after several refusals he consented. Alexander collected an army, drove the Germans out of Pskof and their new fort, and at last (p. 070) defeated them on the ice of Lake Peipus in 1242. This is known as the Battle on the Ice. Alexander then returned to Novgorod where he was received with honor and joy. Andrew, the Grand Duke of Souzdal, Alexander's brother, refused to recognize Bati's authority, whereupon a Tartar army ravaged his territory for the second time. Novgorod, as we have seen, had escaped the Tartar invasion, but when Alexander Nevski received a letter from Bati, in which the khan said, "God has subjected many peoples to me, will you alone refuse to recognize my power? If you wish to keep your land, come to me; you will see the splendor and the glory of my government." The duke thought it prudent to comply. He and his brother Andrew went to Sarai, where honors were showered upon the hero of the Neva. The two brothers were directed to visit the great khan, as their father Iaroslaf had done. They did so; and the Mongol emperor confirmed Andrew as Duke of Souzdal, but to Alexander's dukedom, he added Kief and South Russia. They returned from the Far East in 1257. VIII--RUSSIA UNDER THE MONGOL YOKE. (p. 071)