During the reign of Ivan III important developments promoted to the transformation of Moscow Duchy into the united Russian state. Moscow knayz Ivan III introduced the policy of “lands gathering” and in 1478 conquered Novgorod that was followed by Tver (1485).
Later Ivan III would be proclaimed the Tzar of All Russia.
In 1522 under the rule of Vasily III, the son of Ivan III, Smolensk joined Russian state. In 1520 Ryazan’s annexing completed the unification of Russian lands. It was under Ivan III that Russia stopped paying the tribute to Mongols: the Mongol Yoke was over.