"In medieval times, feelings of Jihad lay behind fighting for the defence of Islam in the Mediterranean basin, such as during the Crusades in the Levant and during the Christian Reconquista of the Iberian peninsula. It was also used for the spreading of Islam outside the heartlands, e.g. into sub-Saharan Africa, in the Indian subcontinent, and in Indonesia. Typical manifestations of this last in West Africa were the Fulani Jihad led by Usumanu dan Fodio (d. 1817) in Hausaland and jihads by Umar al-Futi and Samori Ture in other parts of black West Africa in the 19th century, aimed primarily at spreading the faith among local animists. In Muslim India, notable was the movement of the mujahedin or ‘fighters for the faith’ of Sayyid Ahmad Brelwi (killed 1831), primarily against the Sikhs in the Punjab, and other similar movements against the British which continued throughout the century and into the present one, especially along the North-West frontier. In pre-modern times jihad was not invariably directed against the outside, non-Islamic world; at various times, the slogans of jihad were employed in campaigns against heterodox or dissident Muslims, such as the Ismailis, during the Mongol period and just afterwards."
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Jihad Again was used for defense against intruders and those who oppesed the Islamic faith. if you were not of Islamic faith with jihad they were able to attack you to convert you into Islam or in other words Muslim.
"The decline of the Roman Empire gave rise to two problems, which combined to form one of the most perplexing philosophical questions of late antiquity. On the one hand, Rome found itself under constant military threat as various tribes from the north and east encroached along its borders to fill the power vacuum left by the receding Empire. On the other hand, adherents to the Empire’s new official faith — Christianity — found themselves without clear guidance as to what military roles their faith would permit. The death of the apostles had left Christians without ongoing revelatory guidance, and the New Testament writings alone were not definitive on the subject. The question thus became: ‘Can a Christian answer the Empire’s call to military duty and still have a clear conscience before God?’
Fifth-century philosopher St Augustine of Hippo sought to provide an answer to the question. His approach formed the foundation of the ‘just war’ tradition, which has had enormous influence upon moral-philosophical thought on military issues in the West ever since. This major new study identifies Augustine’s fundamental premises, reconstructs his just-war theory, and critically evaluates the reconstructed theory in light of his historical context and neo-Platonic and Christian philosophical considerations."(Google Book)
1)A punitive conception of war.
2)Assessment of the evil of war in terms of the evil moral attitudes and wants.
3)The authorization of the use of violence.
4)A duelistic epistemology which gives spiritual priorities to goods.
5)Interpretation of evangelical norms in terms of inner attitudes.
6)Passive attitude to authority and social change.
7)use of texts within the Bible to the participation of war.
8)An analogical knowledge of what peace is.
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Just War was the theory that Europeans used to defend themselves against invading infidels. Which is just the Christian version of Jihad which enabled them to attack and defend themselves against the Muslims. With this theory of Just War Europeans were able to fight back and invade Islamic countries, and unlike the Muslims they did not use the convert or die phrase until the 4th crusade. Which until the 4th crusade they did not have hardly any success, it was when the Mongols attacked them from one side and the Europeans on the other did they have any effect on the Muslims.
Just War was used in the crusades in order to take back their Christian and Holy Sites that were taken over by the Muslims during other Crusades or even before the 1st crusade. The Jihad theory or the 6th pillar of Islam was the same thing as Just war during the Crusades except that it was the taking over of the Holy Sites and the Christian relics.(Google Book)
"Of all the churches mentioned in the New Testament, only a single one, Rome, escaped Muslim domination.
In addition, piratical raids and campaigns of raiding on land, slave-taking and slaughter took place virtually every summer for a thousand years, both to acquire plunder, and to destabilise and weaken neighbouring Christian lands. No permanent peace with "infidels" was allowed by Islam.
Islam's scriptures, the Koran, make the approach to non-muslims clear:
"Make war on them until idolatry shall cease and God’s religion shall reign supreme" (8:39)
"Prophet, rouse the faithful to arms. If there are twenty steadfast men among you, they shall vanquish two hundred; and if there are a hundred, they shall rout a thousand unbelievers, for they are devoid of understanding." (8:65)
"Fight against such of those to whom the Scriptures were given ... and do not embrace the true Faith, until they pay tribute out of hand and are utterly subdued." (9:29)
"Slay the idolaters wherever you find them. ... lie in ambush everywhere for them. If they repent and take to prayer and render the alms levy, allow them to go their way ..." (9:5)
The Koran contains many similar verses.
In fact, most Muslim Scholars see the world as divided into two "houses"—the House of Peace (Dar Al-Salaam) and the House of War (Dar Al-Harb). The lands controlled by Muslims belong to the House of Peace, while those who have not yet submitted to Islam belong to the House of War until they are "utterly subdued."
So the entire context of the eastern Crusades is one of response to continuous Islamic aggression."
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