Shadow of a bloody past: For centuries, Islam and Christianity were locked in a brutal conflict most have forgotten. The horror, a top historian argues, is that for jihadis it's as real today as it was in the Middle Ages

The grievances of the Islamic terrorists who have brought carnage and bloodshed to the streets of Paris twice this year reach far back into history.

In their minds, it is not simply wanton violence, but the continuation of a struggle which has raged for more than a millennium.

That is what Osama bin Laden was talking about when he warned the Muslim world back in 1996 'that the people of Islam have always suffered from aggression, iniquity and injustice imposed on them by the Zionist-Crusader alliance'.

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Militant Islam:  ISIS fighters (above) today see themselves as being engaged in a war as old as Islam itself

Militant Islam: Modern-day ISIS fighters see themselves as being engaged in a war as old as Islam itself

Today, ISIS nurtures its resentments in a similarly poisonous manner. 

In the gloating communiqué it released after the terror attacks in Paris last week, France was condemned in decidedly medieval terms: as the capital of 'the Cross'.

This is because jihadis see themselves as being engaged in a war as old as Islam itself: a struggle for global supremacy against Christianity.

Such a reading of history reflects the undoubted fact that both religions have long cast themselves as being destined to prevail across the entire world. The tensions between them, then, are hardly surprising.

There were Christians in the Middle Ages who believed Islam to be nothing more than a heretical plagiarism of their own faith, and Muhammad a giant, jewel-encrusted idol. In a corresponding spirit, the Islamic holy book the Koran accused Christians of having corrupted the Bible.

In the early 7th century, when Muhammad embarked on his prophetic mission, the vast majority of people in the Middle East were Christian.

Yet by 650, fewer than 20 years after Muhammad's death in 632, Arab armies had conquered most of the Middle East, and brought huge numbers of Christians under their rule. 

Fierce battle: The conquest of Constantinople by the Ottoman Turks saw the most famous of Christian capitals transformed into a bastion of Islam. Year after year, Turkish forces probed Christian defences

Fierce battle: The conquest of Constantinople by the Ottoman Turks saw the most famous of Christian capitals transformed into a bastion of Islam. Year after year, Turkish forces probed Christian defences

The emergent empire grew fat on taxes levied upon those who had been conquered.

What, though, of those Christians who refused to submit to the Arabs? 

The Byzantine Empire — the name by which historians call the eastern, surviving half of the Roman Empire — still held out, although it had lost Syria, Palestine and all its North African provinces.

By the 8th century, 100 years after the death of Muhammad, it was becoming clear that the Islamic Caliphate that had been established was not, after all — as Muslims had originally hoped — destined to conquer the world in one fell swoop.

Though they had swept westwards to Morocco and eastwards deep into central Asia, Arab armies had still experienced the occasional rebuff.

Their most formidable foes, as they had been from the very beginning, were the Byzantines, whose capital, the great city of Constantinople, ranked as the bulwark of Christendom.

Both religions have long cast themselves as being destined to prevail across the entire world. The tensions between them, then, are hardly surprising

Twice besieged by the Arabs, it twice stood firm. Ultimately, the Arabs came to view their war with the Byzantines as a grinding stalemate, one destined to endure for numberless generations.

Unsurprisingly, then, during the 8th century, Muslims began to conceive of the world as divided between the House of Islam and a Christian 'House of War', sinister in its disbelief, obdurate in its defiance of the message of the Holy Koran. Sayings became attributed to Muhammad which cast warfare in the cause of the Muslim God as a duty of the Faithful, such as: 'I was ordered to fight all men until they say, 'There is no god but Allah.' '

Slaughtering Christians was cast not merely as an option for dutiful Muslims, but as a positive obligation. One veteran of warfare against the Byzantines gave a blistering retort to a battle-shy friend who had boasted of his peaceable pilgrimages to Mecca and Medina.

'Your worship is mere play. For you the fragrance of spices, but for us the fragrance of dust, and dirt, and blood flowing down our necks — which is altogether more pleasant.'

Meanwhile, in the west of Europe, Christian kings were struggling to reconcile Christ's teaching to turn the other cheek with their own martial instincts. They had little choice.

Arab pirates swept the coasts of Italy and southern France, plundering entire provinces for human booty, while in Spain, Muslims had conquered an empire that left the peninsula's Christians confined like wolves to mountains and barren plains.

Waging war: The grievances of ISIS militants (pictured on the Syria-Iraq border) reach far back into history

Waging war: The grievances of ISIS militants (pictured on the Syria-Iraq border) reach far back into history

Massacre: A bloodied survivor of one of the Paris attacks last week is assisted by a French police officer

Massacre: A bloodied survivor of one of the Paris attacks last week is assisted by a French police officer

Al-Andalus, as this western Caliphate was known — modern Andalucia — was as brilliant as any region in the House of Islam: rich with crops, studded with great cities, and adorned with the arts of peace such as science and philosophy.

Even its Christian enemies hailed it as 'the ornament of the world'. Certainly, the strife-torn and poverty-stricken kingdoms of Christendom had nothing to compare. Their backwardness, to the Muslims of al-Andalus, appeared the natural order of things.

In 997, in demonstration of this, a Muslim army sacked Santiago de Compostela, Spain's holiest Christian shrine.

Bells from the despoiled cathedral were suspended from the Great Mosque of Cordoba in the south, to serve the faithful as lamps, and prisoners of war set to labouring on a great extension to the mosque.

Others were publicly decapitated, and their severed heads paraded through the market place, before being hung from the main gates of the citadel.

Today, according to a poll, some two-thirds of Muslims worldwide want to see the restoration of a Caliphate. It is not empires per se they are opposed to — just non-Islamic empires

Yet, despite blows such as these, Christendom did not collapse. Instead, in the age of the Crusades it began to go on the offensive. Summoned by the Pope in 1096 to defend the holy sites of Jerusalem, hordes of Christian warriors set off from Western Europe for the Holy Land. 

Three years later, on July 15, 1099, a Christian army broke into Jerusalem; and this time it was the streets of Islam's third holiest city that flowed with blood.

At the end of it, when the slaughter was done, the triumphant warriors of Christ, weeping with joy and disbelief, assembled before the sepulchre of their Saviour and knelt in an ecstasy of worship.

The success of the Crusaders reflected a militarisation of Christian doctrine that rendered it more than the equal of Islam's own commitment to martial violence.

Even though Jerusalem remained in their hands for less than a century, other triumphs proved more enduring. In the 11th century, Sicily was seized back from its Muslim rulers by the Normans, while al-Andalus was progressively reconquered by the Christians of Spain. Not that most Muslims despaired. They scorned Europe as barbarous, fragmented and impoverished, full of shamelessly immodest women and men who never washed.

Their horizons were infinitely broader. By the 15th century, a continuous chain of Muslim lands had come to stretch from the Atlantic to the China Sea.

Horrific: Rescue workers help a woman after the shooting, outside the Bataclan theater in Paris last Friday

Horrific: Rescue workers help a woman after the shooting, outside the Bataclan theater in Paris last Friday

Politically fragmented this empire may have been, yet, wherever Muslims travelled, they could hear the Arabic of the Koran, and glory in the certitude that there was only one true global faith: Islam.

In 1453 came an event which suggested the Muslim faith might become more universal still. 

The conquest of Constantinople by the Ottoman Turks saw the most famous of Christian capitals transformed into a bastion of Islam. With much of the Balkans already under Ottoman rule, it seemed as though Europe might after all fall to Islam.

Year after year, Turkish forces probed Christian defences, crossing the plains of Hungary, or churning the waters off Malta with their warships. In 1529, and again in 1683, an Ottoman army almost took Vienna.

Yet that was to be the last great attempt to extend the Caliphate across Europe. The global balance of power was shifting, and nearly a millennium of Muslim preponderance was drawing to a close.

No one should doubt the dangerous nature of the memories that ISIS is playing with

It was Christians who colonised America, established trading empires that spanned the globe and started the process of industrialisation. By the 19th century, with India ruled by the British Raj, and the Islamic Ottoman Empire scorned in Western capitals as 'the sick man of Europe', Muslims could no longer close their eyes to the sheer scale of their decline.

It was they who were now the imperial subjects, and Islam the civilisation looked down on by its adversaries as backward, as Christendom had once been.

Ever since the first days of their faith, Muslims had tended to take for granted that its truth was manifest in its worldly success.

As a result, subordinated to the infidel British or French, there were many in the Muslim world who looked to the golden age of the Caliphate for their inspiration.

The age of Muhammad and his successors, which had seen Islam emerge from desert obscurity to global empire, was enshrined as the model to follow. Over recent decades, resentment at continued Western interventions in Muslim countries such as Afghanistan and Iraq have only burnished the appeal of the glorious past.

Dark shadow: The jihadi dream of a return to a world split into two violently divided rivals — into a 'House of Islam' and a 'House of War' — no longer seems such a fantasy as once it did. Above, an  ISIS fighter in Syria

Dark shadow: The jihadi dream of a return to a world split into two violently divided rivals — into a 'House of Islam' and a 'House of War' — no longer seems such a fantasy as once it did. Above, an  ISIS fighter in Syria

Today, according to a poll, some two-thirds of Muslims worldwide want to see the restoration of a Caliphate. It is not empires per se they are opposed to — just non-Islamic empires.

Hardly surprising, then, that al-Qaeda and ISIS should be so obsessed by periods of history that to most Westerners are thoroughly obscure.

That Constantinople has been a Muslim city for almost 600 years, that the Crusades are done and dusted, and that Europe no longer defines itself as Christendom, barely intrudes on the consciousness of many jihadis.

They inhabit a mental landscape in which the Middle Ages never went away. The menace of this way of thinking is brutally evident — a world in which young people murdered at a rock concert can be cursed as 'Crusaders' is a world on the verge of going mad.

It is not just non-Muslims who are threatened by this imperialist nostalgia. 'Either you are with the Crusade,' ISIS has warned European Muslims, 'or you are with Islam.'

Its ambition is to terrorise the West into turning against its own Muslim citizens, and render it impossible for them to live here as equals: 'For then Muslims in the Crusader countries will find themselves driven to abandon their homes, and will go to live in the Caliphate.'

History could hardly be more brutally exploited.

No one should doubt the dangerous nature of the memories that ISIS is playing with. 

And the jihadi dream of a return to a world split into two violently divided rivals — into a 'House of Islam' and a 'House of War' — no longer seems such a fantasy as once it did.

The shadow of the past is growing darker over Europe, and the world.

  • Tom Holland is the author of In The Shadow Of The Sword and Millennium.  

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