Regnal name

A regnal name, or reign name, is a name used by some monarchs and popes during their reigns. 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 name different from their own usual personal name when they inherit a throne.

The regnal name is followed by a regnal number (ordinal), usually expressed as a Roman numeral (VI rather than 6), to provide a unique name for that monarch. If a monarch rules more than one realm, he or she may carry different ordinals in each one, as they are each assigned chronologically, but some realms may have had different numbers of rulers of the same regnal name previously, usually from a different dynasty. For example, one ruler was both King James I of England (along with Ireland) and King James VI of Scotland.

The ordinal is not always used for the first ruler of the name, but is used in historical references once the name is used again.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I of England was called simply "Elizabeth of England" until the accession of Queen Elizabeth II in 1952; subsequent historical references to the earlier figure were changed to Elizabeth I. However, Tsar Paul I of Russia, King Umberto I of Italy, King Juan Carlos I of Spain, and Pope John Paul I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.