Regardless of the official traditions in the various colonial empires, the style is evidently used to render, often merely informally, various somewhat analogous titles in non-western cultures, regardless whether there is an actual linguistic and/or historical link.
In Samoa, for example, the heads of the four paramount dynasties carry the title of His/Her Highness. Both the current and previous Heads of State are styled His Highness. Furthermore, in North America, some chiefs of certain tribes or nations use the attribute of Highness.
The present Aga Khan was granted the style of 'His Highness' by Elizabeth II, Queen of the United Kingdom in 1957 upon the death of his grandfather Aga Khan III. This has been a traditional gesture by British sovereigns since the first Aga Khan allied himself with Britain against Afghanistan
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