This is the beginning of the story of Achilleus as told in the Iliad: The Thirteenth Century BC war between the Trojans and the Greeks has dragged on for years in the low-key way that primitive warfare generally does, lots of noise, lots of display, relatively few actual casualties. But the war has gone on for a while, and over time the casualties have not been light. Both sides feel economic pressure to end the war, everyone is growing impatient. Then Achilleus, the most formidable warrior on either side, withdraws from the fighting, seriously unbalancing the situation. The two sides try to settle the conflict with a duel, but the duel’s result is ambiguous, both sides snap, and something on the level of modern warfare breaks out.
People had no clear idea of why they were fighting. The Greeks did not care all that much for Menalaos, and the Trojans cared even less for Helen and not at all for Paris. Giving back Helen is the obvious thing to do at every point yet they never quite do it, something happens or the discussion simply trails off. Something similar happens in the Volsungasaga. Hogni and Gunnar know perfectly well that they should not accept Atli’s invitation, everyone tells them not to go, it is obvious that they should not go, and they freely say that they should not. They know exactly what they should do, yet they can never quite make up their minds to do it. The warriors in the Iliad go to their deaths through no desire of their own and no reason that they can understand. They knew only that Fate had them in its grasp, and they were helpless against it. They could do nothing but fight this hopeless battle with every ounce of strength in their souls, though there was nothing for them to win but a few more days or a few more years until their death, and perhaps posthumous glory.