I didn't see anything in the parent comment about assassination, but given the topic: Yes, when governments were effectively embodied by one single person invested with something approaching absolute power, bumping off that person would change the situation. Of course it often plunged the kingdom into some type of crisis until the succession was decided and a new monarch/king/whatever was installed. That's still the case in some countries, like what happened in Iraq w/ Saddam Hussein (yes, it was more complicated than that, I know) But in other countries that have some flavor of democracy, bumping off the person in charge is not really a path to changing the social/economic order. The power structures go way beyond a single individual, and continuity is fairly well preserved.