Most Faithful Majesty
The sobriquet Most Faithful King (Latin: Rex Fidelissimus, Portuguese: Rei Fidelíssimo) was a title awarded by the Pope Benedict XIV – as spiritual head of the Catholic Church – in 1748, to the King John V of Portugal and to his heirs.
The title Fidelissimus remains attached to monarchs descended from whoever received the original sobriquet. The sobriquet can be awarded to either a king or a queen. The only European monarchy that has received the sobriquet was the now-defunct monarchy of Portugal.
- Verzijl, J. H. W. (1973). International law in historical perspective / 6, Juridical facts as sources of international rights and obligations. Leiden: AW Sijthoff. pp. 164, 174. ISBN 9789028602236.