Explanation: The Roman Emperor Valentinian I died during negotiations with some Germanic tribes because the famously hot-tempered Emperor finally blew one fuse too many! When the Quadi tribe insisted that the conflict was the fault of the Romans, and that the Quadi were not bound by any treaties they made, Valentinian had a stroke while shouting at their envoys.
Best part is, old age isn't even certain - there were assassination rumors swirling around Augustus's death too. Never a dull moment as the most powerful autocrat in the Classical world!