According to wikipedia, that guy committed sepuku?
I was pretty sure I was thinking of some european leader, too. Perhaps not a king, though, but someone of great importance.
Found mention of a soldier named Tychon described in a medical text, "Of the Epidemics", written by Hippocrates. Could be the guy? He got shot in the back with an arrow, but it was at an angle where it was easily removed so they yanked it out and didn't even think about it until the lockjaw set in.
