It was the custom for soldiers to demand ransom for the safe return of prisoners taken in battle. The more important the prisoner or the higher his rank or position within the army or government, the higher the ransom. This brings into question Henry's order to kill all the prisoners his army had taken in the battle; in an act of vengeance against the French attack on the English baggage and attendants ("kill the boys and the luggage"), Henry is denying a traditional source of financial gain to his own soldiers — and breaking a fundamental, albeit unwritten, chivalric "law" of warfare. (To be fair, the French attack on the baggage train was another such infraction, as Fluellen complains — but do two wrongs make a right?)