Throne name

A regnal name, or reign name, is a name used by some monarchs and popes during their reigns, and used subsequently to refer to them. The term is simply the adjective "regnal", of or relating to a reign, monarch, or kingdom, modifying "name". Since ancient times, monarchs have frequently, but not always, chosen to use a different name from their original name when they accede to the monarchy.

The regnal name is usually followed by a regnal number (ordinal), usually written as a Roman numeral (VI rather than 6), to provide a unique identification for that monarch among other monarchs of that realm. In some cases, the monarch has more than one regnal name, but the regnal number is based on only one of those names, for example Charles X Gustav of Sweden, George Tupou V of Tonga. If a monarch reigns in more than one realm, he or she may carry different ordinals in each one, as they are each assigned chronologically, and some realms may have had different numbers of rulers of the same regnal name previously. For example, the same person was both King James I of England (along with Ireland) and King James VI of Scotland.

The ordinal is not normally used for the first ruler of the name, but is used in historical references once the name is used again. Thus, Queen Elizabeth I of England was called simply "Elizabeth of England" until the accession of her descendant, Queen Elizabeth II almost four centuries later in 1952; subsequent historical references to the earlier queen retroactively refer to her as Elizabeth I. However, Tsar Paul I of Russia, King Umberto I of Italy, King Juan Carlos I of Spain, and Pope John Paul I all used the ordinal I (first) during their reigns, while Pope Francis does not. In spoken English, such names are pronounced as "Elizabeth the First", "George the Sixth" etc.

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