Causal Loops: Normally in this kind of situation, the narrator survives the battle, then jumps back with additional power to help himself survive. A causal loop in that he sees himself on the battlefield, therefore he comes back to the battlefield, therefore he sees himself. . .
Free Will, Fate, and Determinism: So why does he come back? Perhaps because he knows (having seen himself) that it is fated. Or perhaps because he knows that if he doesn’t come back that he’ll die then and there at the hands of the Mongols.
You get attacked, you have no backup, so you become your own.
1 English variant