Serene Highness is a style of address used by several princely and noble families thoughout present day Europe. It has also been used historically. It ranks below Royal Highness and Imperial Highness.
Examples of usage
- Princes of the Blood at the French royal court of Versailles. (Such as His Serene Highness The Duke of Penthièvre).
Serene Highness for Kids. Kiddle Encyclopedia.