Why are there numbers in the end of famous politicians or great kings or queens names? ? ex: queen elizabeth i govinda iii krishna ii plzz

Since ancient times, some monarchs have 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, written as a Roman numeral, to differentiate that monarch from others who have used the same name while ruling the same realm.

answer; does not include a reference to the audience;