The insane wars of the Jaredite chiefs ended in the complete annihilation of both sides, with the kings the last to go. The same thing had almost happened earlier in the days of Akish, when a civil war between him and his sons reduced the population to thirty… . This all seems improbable to us, but two circumstances peculiar to Asiatic warfare explain why the phenomenon is by no means without parallel:
This is clearly seen in the game of chess, in which all pieces are expendable except the king, who can never be taken. ‘The shah in chess, ’ writes M. E. Moghadam, ‘is not killed and does not die. The game is terminated when the shah is pressed into a position from which he cannot escape. This is in line with all good traditions of chess playing, and back of it the tradition of capturing the king in war rather than slaying him whenever that could be accomplished.’
You will recall the many instances in the book of Ether in which kings were kept in prison for many years but not killed. In the code of medieval chivalry, taken over from central Asia, the person of the king is sacred, and all others must perish in his defense. After the battle the victor may do what he will with his rival—and infinitely ingenious tortures were sometimes devised for the final reckoning—but as long as the war went on, the king could not die, for whenever he did die, the war was over, no matter how strong his surviving forces.
Even so, Shiz was willing to spare all of Coriantumr’s subjects if he could only behead Coriantumr with his own sword. In that case, of course, the subjects would become his own. The circle of warriors, ‘large and mighty men as to the strength of men’ … that fought around their kings to the last man, represent that same ancient institution, the sacred ‘shieldwall, ’ which our own Norse ancestors took over from Asia and which meets us again and again in the wars of the tribes, in which on more than one occasion the king actually was the last to perish. So let no one think the final chapter of Ether is at all fanciful or overdrawn. Wars of extermination are a standard institution in the history of Asia.
It is impossible for us to fully fathom the horror of the final Jaredite battle in which even women and children were armed and sent to war (see Ether 15:15). Here we have a graphic picture of what men become when the Spirit of the Lord withdraws and no longer strives with them (see v. 19).
(Hugh Nibley, Lehi in the Desert and the World of the Jaredites, pp. 235–36)