The marriage of Zoe/Sophia (Thomas's second daughter) to Ivan III of Moscow served to strengthen Moscow's claim to be the "Third Rome", the ideological and spiritual successor to the Byzantine Empire. Sophia and Ivan had several children and numerous descendants. Though the Palaiologos name was not passed on, many of them used the double-headed eagle iconography of Byzantium. The famous Ivan the Terrible (1547–1575), Russia's first Tsar, was Sophia's grandson. The Romanov dynasty, which succeeded Ivan the Terrible's Rurik dynasty and ruled Russia from 1613 to 1917, were not descended from Sophia, originating as in-laws, rather than descendants, of the Rurikids.