It is even more complicated IRL : a king can have several numbers related to its different titles.
The best exemple may be a famous guy who was :
- Charles II duke of Brabant
- Charles Ist (Carlos I) king of Spain and America
- Charles IV (Carlo IV) king of Sicily
- Charles V (Karl V) Holy Roman Emperor
As he was best remembered as Holy Roman Emperor though, Spaniards tend to remember him as Carlos V :rofl:
The best exemple may be a famous guy who was :
- Charles II duke of Brabant
- Charles Ist (Carlos I) king of Spain and America
- Charles IV (Carlo IV) king of Sicily
- Charles V (Karl V) Holy Roman Emperor
As he was best remembered as Holy Roman Emperor though, Spaniards tend to remember him as Carlos V :rofl: