Commemorative stamp of the Proclamation of H.M. King Juan Carlos I of Spain with Doña Sofía. Juan Carlos de Borbón y Borbón was proclaimed King of Spain by the Spanish Courts as Juan Carlos I of Spain on November 22, 1975 and exalted to the throne on November 27 with an anointing ceremony called Misa de Espíritu Santo (the equivalent of a coronation), held in the historic Church of San Jerónimo el Real in Madrid.