Jus ad Bello; Just Cause- The only reason to start a war is in defense. Pope Urban II was trying to ask volunteers to come to his aid from the invading Turks as an appeal to the Byzantine Empire, however, he wasn't attacked and therefore had no right to do this.
Jus in Bello; Proportionality- The war must end before it becomes a massacre. Muslims and Jews were being slaughtered in mass amounts, burned, and only a few were lucky enough to survive after escaping or being ransomed off.
Jus in Bello; Right Intention- The aim of political and military leaders must be peace with justice. Although the intention of the crusades was to regain Jerusalem and other European areas, all of the Muslims and Jews were killed and segregated.
Jus in Bello; Noncombatant Immunity- War must discriminate between combatants and noncombatants. Peasants along with Jews and Muslims weren't supposed to be involved in the fighting, but were killed nevertheless.
Right Intention- The aim of political and military leaders must be peace with justice. Not only did the English lust after land and money without any right intention, but when the French didn't give, in they went to war with them.
Last Resort- All non-violent options must be tried before waging war. Henry V could have come to a mutual agreement, however, he still wanted land, money, and power.
Noncombatant Immunity- In war, combatabts must be avoided or minimize even indirect harm to civilians. Henry V ordered the slaughter of about several thousand noncombatant French prisoners. He feared that they would rebel against him.
Probability of Success- War is only just if fought with a reasonable chance of success. Although the French had twice the amount of troops than the English, Henry V still went on to war.
Right Intention; The aim of political and military leaders must be at peace with justice. The Popes rejected all compromise with the Protestants just because of their Catholic faith. This isn't being indiscriminate with all the parties involved.