But there are precedents.

Take the eerily similar story of the Almohads, a fanatical Moroccan sect that rose to power in the twelfth century. Born deep in the Maghrib and led by a self-styled caliph, the Almohads toppled moderate states in North Africa and Southwest Europe in order to impose a puritanical Islamic society. That society bore images frighteningly similar to those seen in present-day Iraq and Syria: crucifixion, enslavement, massacre, and the expulsion of non-Muslims.

The Almohads were followers of a fiery preacher named Mu?ammed ibn Tûmart. Tûmart denounced the corruption of the region’s ruling order and in the 1120s led an insurgency from the Atlas Mountains. The insurgency reached a stalemate by the time of Tûmart’s death in 1139; thereafter, a factional leader named ‘Abd al-Mu’min took control of the insurgency, declared himself caliph, and continued the struggle. ¹

Under their caliph’s stewardship, the Almohad warriors waged a renewed jihâd with great fervor, sweeping across virtually the whole of the Maghreb. Disenfranchised Berber tribes, opportunistic élites, and religious fundamentalists flocked to the Almohad cause, filling Mu’min’s ranks and extending his reach. The young caliphate’s victories caught the attention of Muslim leaders across the Gibraltar Strait, who were in desperate need of aid against the Christian armies of Europe. The caliph was more than happy to take advantage of this opportunity.

The first Almohad warriors landed on European soil in the 1140s, spreading into the Iberian hinterland to eventually seize the great cities of Almería, Córdoba, Sevilla, and València.  Within a generation, the Almohads controlled approximately 40 percent of the peninsula.

Much of the Almohads’ success came from a valuable combination of discipline, inspiration, and order. Almohad warriors genuinely believed themselves to be doing God’s work, regardless of how cruel that work might appear.

And cruel it was. The Almohad occupation may have brought security to Southern Iberia, but that security brought with it harsh and intolerant singularity to what had once been a richly multicultural society. “Impious” texts, those that did not conform to strictly Islamic tenets, were stripped from libraries and destroyed. Scholars deemed subversive to the new order were ousted and imprisoned. Dissidents to the theocracy were subject to public crucifixion. ²  Christians and Jews were given the choice of conversion to the Islamic faith or death.

Unsurprisingly, there was a massive exodus from the Almohad realm. Christians might at least find sanctuary with coreligionists to the north, but Jews faced a more uncertain fate. The resulting persecution saw prominent non-Muslim scholars, most notably Moshe ben Maimon, flee to more tolerant lands in the Eastern Mediterranean. The Almohads succeeded in creating a wholly Islamic order in Southern Iberia, all the while ending a multi-religious and cosmopolitan renaissance.

 

The Almohads benefited greatly from the division of their enemies. The Christian Iberian states of Aragon, Castile, Leon, Navarre, and Portugal were in an almost constant state of hostility with one another. The caliph played a game of divide-and-conquer, forming a temporary treaty with one state in order to assault another, consolidate his gains, and then strike at his treaty partner.

By the 1200s, the caliphate had inched into Central Iberia and taken the strategically valuable Balearic Islands, an excellent staging point for expansion into the Northwest Mediterranean.

That fact sobered Christian Europe for the need to take action. The archbishop of Toledo, Rodrigo Jiménez, called for Europe’s Christian rulers to unite against the Almohad forces. The pope, seeing the severity of Almohad threat, ordered a crusade to crush the caliphate once and for all.

Volunteers from across the continent and Britain flocked to aid the Spanish cause. In a rare instance of solidarity, the Christian rulers of the peninsula agreed to a joint campaign against the caliph. In the summer of 1212, the kings of Aragon, Castile, and Navarre met at Toledo. After agreeing on a strategy, the three monarchs marched south against the caliph.  

It turns out that the timing of the campaign could not have been better: Mu?ammad an-Nâ?ir, the fourth Almohad caliph, was preoccupied with revolts in Northwest Africa. The report of a massive Christian offensive forced Nâ?ir to suspend his efforts in the Maghreb and hurry back to Iberia, where he hastily mobilized the semblance of a force to intercept the European coalition.

That point of interception would be at Las Navas de Tolosa in the valley below the Sierra Morena. Nâ?ir expected the dense mountain range to provide an effective buffer while he set up camp. Unbeknownst to the caliph, Christian forces navigated through a little-known pass along a gorge.  Nâ?ir awoke on the morning Monday, July 16, to find three European armies facing him and holding the high ground. ⁴

Almohad zeal proved not enough in the ensuing mêlée. Christian forces overwhelmed the Muslim defenders, quickly descending on the caliph’s tent. Nâ?ir, finding all hope lost, abandoned the camp and raced away from the battlefield, leaving behind thousands of his warriors to perish. Nâ?ir did not have long to enjoy his survival from battlefield, dying the following year.

His caliphate never recovered. The Almohads were soon forced to relinquish vast swathes of territory to Christian invaders and Muslim rebels, all of whom sensed that momentum was on their side. By 1240, most of the Almohad empire had vanished. By the 1260s, the caliph’s once-great domain consisted of a mere residence in Marrâkesh. By 1270, the dynasty was extinct. ⁵

In hindsight, the Almohads’ most distinguished attributes–puritanical fervor and immense conquests–proved their greatest liabilities. The caliphate’s fervor and puritanism brought order to a fractious region; yet it also created a harsh, intolerant society that fostered discontent far and wide. The speed and scale of the Almohads’ conquests seemed clear proof of divine grace; yet, conversely, those conquests finally drove the dynasty’s enemies to unite and take decisive action in order to halt, and eventually shatter, the caliphate.

The Almohads left behind an enduring legacy, one that demonstrated how the most ignoble of movements could dramatically and violently shape the course of a region.