War well into the 1450s. Although he was ousted from Moscow on several occasions, taken prisoner by Olug Moxammat of Kazan, and blinded in 1446, Vasily II eventually managed to triumph over his enemies and pass the throne to his son. At his urging, a native bishop was elected as Metropolitan of Moscow, which was tantamount to a declaration of independence of the Russian Orthodox Church from the Patriarch of Constantinople (1448). Ivan III Outward expansion of the Grand Duchy in the 14th and 15th centuries was accompanied by internal consolidation. By the 15th century, the rulers of Moscow considered the entire Rus' territory their collective property. Various semi-independent princes of Rurikid stock still claimed specific territories, but Ivan III (the Great; r. 1462–1505) forced the lesser princes to acknowledge the grand prince of Moscow and his descendants as unquestioned rulers with control over military, judicial, and foreign affairs. Moscow gained full sovereignty over a significant part of the ethnically Rus' lands by 1480, when the overlordship of the Tatar Golden Horde officially ended after its defeat in the Great Stand on the Ugra River. By the beginning of the 16th century, virtually all those lands were united, including the Novgorod Republic (annexed in 1478) and the Grand Duchy of Tver (annexed in 1485). Through inheritance, Ivan was able to control the important Principality of Ryazan, and the princes of Rostov and Yaroslavl' subordinated themselves to him. The northwestern city of Pskov, consisting of the city and a few surrounding lands, remained independent in this period, but Ivan's son, Vasili III (r. 1505–33), later conquered it. Having consolidated the core of Russia under his rule, Ivan III became the first Moscow ruler to adopt the titles of tsar and "Ruler of all Rus'". Ivan competed with his powerful northwestern rival, the Grand Duchy of Lithuania, for control over some of the semi-independent former principalities of Kievan Rus' in the upper Dnieper and Donets river basins. Through the defections of some princes, border skirmishes, and the long inconclusive Russo-Lithuanian Wars that ended only in 1503, Ivan III was able to push westward, and the Moscow state tripled in size under his rule. The reign of the Tsars started officially with Ivan the Terrible, the first monarch to be crowned Tsar of Russia, but in practice, it started with Ivan III, who completed the centralization of the state (traditionally known as the