Emperor Yūryaku (雄略天皇) was the 21st imperial ruler of Japan. No firm dates can be assigned to this emperor or to his reign, but he is believed to have ruled the country during the late 5th century CE.
... designated anyone who assumed power for any period of time without a legitimate basis of authority.
The first to have the title of "Tyrant" was Pisistratus in 560 ...