Gaston, Duke of Orléans, younger son of King Henry IV of France, encountered the style in Brussels and assumed it himself.
[1] By the 18th century, Royal Highness had become the prevalent style for members of a continental reigning dynasty whose head bore the hereditary title of king or queen.
After dissolution of the Holy Roman Empire in 1806, several of Germany's prince-electors and other now sovereign rulers assumed the title of grand duke and with it, for themselves, their eldest sons and consorts, the style of Royal Highness (Baden, Hesse, Mecklenburg, Saxe-Weimar).
The vast majority of African royalty that make use of titles such as prince, chief and sheikh, eschew the attendant styles often encountered in Europe.
He (or She) whose words are beyond question) is likewise used as the equivalent of the HRH and other such styles by this class of royalty when rendering their full titles in the Yoruba language.
[citation needed] Furthermore, the wives of the king of the Zulu peoples, although all entitled to the title of queen, do not share their husband's style of Majesty but instead are each addressed as Royal Highness, with the possible exception of the great wife.
[citation needed] At the Congress of Vienna in 1815, the former empress Marie Louise of France was restored to her Imperial and Royal style and granted the title of Duchess of Parma, Piacenza and Guastalla, as well as being restored to her premarital title of Archduchess and Imperial Princess of Austria, Royal Princess of Hungary, Croatia and Bohemia.
[citation needed] The title of "Prince/Princess of the Burma with the accompanying style of HRH; direct translation of Burmese: Myint Myat Taw Mu Hla Thaw.
In Burmese Royal order called for Prince: Shwe Ko Daw Gyi Phaya; Taw Phya.
That is the case for example of the children of the younger brother of King Willem-Alexander, Prince Constantijn, who were given the titles of "Count/Countess of Orange-Nassau" and the honorific predicate of "Jonkheer/Jonkvrouw van Amsberg", both hereditary in the male line.
[6] In Norway the style of Royal Highness is reserved for the children of the monarch and the eldest child of the heir apparent.
[12] Finally, a regent designated outside of the royal family in the cases provided by law would bear the simpler style of Highness.
[15][16] O'Neill was not granted royal status and has remained a private citizen, since he wished to retain his British and United States citizenships and his business.
[19] Three of the sisters of King Carl XVI Gustaf were granted honorary titles of Princess (without nationality) when they married commoners but lost their Royal Highness status, as did two of his uncles earlier in the 20th century.
[32] Letters patent dated 21 August 1996 stated that the wife of a member of the royal family loses the right to the style of HRH in the event of their divorce.