Sancho III of Navarre
King Sancho III of Navarre conquered Leon in 1034 and began using it. His son, Ferdinand I of Castile also took the title in 1039. Ferdinand's son, Alfonso VI of León and Castile took the title in 1077. It then passed to his son-in-law, Alfonso I of Aragon in 1109. His stepson and Alfonso VI's grandson, Alfonso VII was the only one who actually had an imperial coronation in 1135.