Catholic majesty
The titles of Catholic King and Catholic Queen are bestowed by the Pope, head of the Roman Catholic Church, on monarchs who, in the eyes of the Church, express Catholic principles in both politics and private life. The title, like the title of nobility, is hereditary and passes to the successor of the one who received it personally.
The best known examples of the award of the title are Isabella I of Castile and Ferdinand II of Aragon (both kingdoms are now part of Spain). According to the Spanish constitution, the Spanish kings can use the title “His Catholic Majesty” (“Su Majestad Católica”). A special right of Catholic queens and princesses is the privilège du blanc .