Several monarchs had titles used in diplomatic settings which were not part of their official national royal style, but which signified their nationality. The Treaty of Paris (1763) is an example of the use of these "treaty titles".
- August Majesty – Holy Roman Emperor
- Apostolic Majesty – King of Hungary
- (Most) Catholic Majesty – King of Spain
- (Most) Christian Majesty – King of France
- (Most) Faithful Majesty – King of Portugal
- Orthodox Majesty – King of Poland
- Prussian Majesty – King of Prussia
- Sicilian Majesty – King of the Two Sicilies
- Britannic Majesty – King of Great Britain, King of the United Kingdom