[ Listen to me Sango. They hate the Emperor enough to want him dead, but they have so far not been able to achieve that, do you know why ].
The Emperor is a leader with lots of people under his command, but that isn't the only thing that made him exceptional.
Before he got to the position he is in now, he has established himself and made a name for himself as one with natural strength gotten from his racial features.
The Viking race are naturally blessed, gifted with strength, the kind that would need about ten average men to take on one average viking.
What more of the Emperor who has lived for a very long time and has honed himself through battles and countless experiences?
That sort of man passing away at the hands of another is sure to spike up a curiosity concerning who killed him.
To further things, the death of the Emperor of the Abranyth Empire is not something that can be kept covered forever.