Tsar Ivan IV (3 September 1530 ??28 March 1584), commonly known as Ivan the Terrible, was the Grand Prince of Moscow from 1533 to 1547 and Tsar of All the Russias from 1547 until his death in 1584. His long reign saw the conquest of the Khanates of Kazan, Astrakhan and Siberia, transforming Russia into a multiethnic and multicontinental state spanning approximately 4,046,856 km2 (1,562,500 sq mi).

Ivan managed countless changes in the progression from a medieval state to an empire and emerging regional power, and became the first ruler to be crowned as Tsar of All the Russias.