He was the first person to be crowned "Tsar of All Russias"

On January 16, 1547, at the age of 16, Ivan was crowned at the Moscow Kremlin's Cathedral of the Dormition. The Metropolitan bestowed royal dignity on Ivan, including the Cross of the Life-Giving Tree, barmas, and the Monomakh cap; Ivan Vasilievich was anointed with myrrh, and the tsar was blessed. He was the first person to be crowned "Tsar of All Russias", partly in imitation of his grandfather, Ivan III the Great, who held the title of Grand Prince of All Rus. Until then, Muscovy's rulers had been crowned as Grand Princes, but in his correspondence, Ivan III the Great referred to himself as "tsar." Ivan married his first bride, Anastasia Romanovna, a Romanov family member who became the first Russian tsaritsa, two weeks after his coronation.

By becoming tsar, Ivan sent a message to the world and to Russia that he was now the country's sole ruler, and his will was not to be questioned. The new title represented the assumption of powers comparable to and analogous to those possessed by the previous Byzantine Emperor and the Tatar Khan, both described as Tsar in Russian sources. The political result was that Ivan's status was elevated. The new title not only safeguarded the throne but also provided Ivan with a new level of authority that was inextricably linked to religion. As church writings described Old Testament rulers as 'Tsars,' and Christ as the Heavenly Tsar, he was now a divine leader sent to carry out God's purpose.