This is the kind of phraseology that indicates the pleasures of an as yet un-codified language. If someone said this now, we’d likely to correct them. “Do you mean, ‘How did he die?’“ And something about this being phrased like that stays with deadness more than asking how someone died. It means the same thing, of course, but the repetition of dead – and “how came” gives it a finality. It points more to the events that led to the death.