Final answer:
Ivan III influenced the development of Russia by ending tribute payments to the Mongols and expanding the Kremlin. He did not name himself tsar, that title was adopted by his grandson. The conversion of Kievan Rus' to Orthodox Christianity was initiated by Prince Vladimir I of Kiev.
Step-by-step explanation:
Ivan III, also known as Ivan the Great, played a significant role in influencing the development of Russia. He ended tribute payments to the Mongols, asserting Russia's independence and laying the foundation for the Russian Empire. Ivan III also made significant architectural changes, bringing in foreign architects to rebuild Moscow and expanding the Kremlin. However, he did not name himself tsar; that title was later adopted by his grandson, Ivan IV (Ivan the Terrible).
Additionally, it was Prince Vladimir I of Kiev who was the first Russian leader to convert to Orthodox Christianity and formed an alliance with the Byzantine emperor Basil II. He married Anna, Basil II's sister, and the conversion of Kievan Rus' to Orthodox Christianity led to the appropriation and adaptation of Byzantine art and architecture in Russia.