I'm a history teacher. While I can appreciate the perspective of Hugo Vickers, it's also true that the date of actually succeeding to a throne has normally been the date of the death of the predecessor. There have been multiple instances of a "minor" succeeding to a throne - more examples would be Mary, Queen of Scots(7 days old), Peter the Great (10 yrs old), Edward VI (9 yrs old), Charles IX(10 yrs old) and others. Should we also count their reigns from the time they because "adult" enough to rule alone?
I don't necessarily disagree with the idea. I'm just a traditionalist who prefers to count the beginning of a new reign as of the date of death of the last monarch.
Hugo Vickers argues that, because the beginning of Louis's reign was a regency, the Queen is actually already the world's longest-reigning monarch. https://www.tatler.com/article/why-the-queen-is-technically-the-worlds-longest-reigning-monarch?utm_medium=Social&utm_campaign=SocialFlow&utm_source=Twitter
This would actually happen on 26 May 2024 when Her Majesty’s reign would be 26,408 days to Louis XIV’s 26,407.
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