There is a theory that 'Homudawake' (in "Nihonshoki" and "Kojiki," Chinese characters used are different) which is thought to be the posthumous name of Emperor Ojin was a real name used when he was alive.
応神天皇の名とされる「ホムダワケ」（『日本書紀』では誉田別、『古事記』では品陀和気と表記）は、実は生前に使われた実名だった、とする説がある。