Despite all this convoluted intrigue, news of al-Salih’s death eventually leaked out, causing alarm and unrest in Cairo. Before long, Louis IX also discovered that, as he later put it, ‘the sultan of Egypt had just ended his wretched life’–tidings that only increased the king’s hopes for victory.39

The main challenge now confronting the crusaders was somehow to breach the physical barrier of the fast-flowing Tanis River. Louis’ stratagem, seemingly formulated in Damietta, was to build a causeway ‘constructed of timber and earth’ across the river. To achieve this goal, the king instructed his chief engineer Joscelin of Cornaut to oversee a two-stage plan. A pair of ‘cat-houses’–movable towers with extending ‘cats’, or protective screens–were raised, under which labourers would be able to work on the causeway. At the same time, some eighteen stone-throwing engines brought from the coast were erected to provide covering fire. Once all these contraptions had been assembled and manoeuvred into position, the second, more perilous, phase of actual causeway construction began.

Unfortunately for the Franks, the Egyptian army had its own battery of sixteen ballistic engines on the south bank of the Tanis. As soon as the crusaders came into range, Fakhr al-Din initiated an incessant bombardment, ‘using relays of men day and night’ to sustain a constant barrage of ‘stones, javelins, arrows [and] crossbow bolts [that] flew as thick as rain’. Like so many Muslim armies before them, the Ayyubids stationed at Mansourah also held a deadly technological advantage over their Christian foes: a ready supply of highly combustible Greek fire (or, as one Frank aptly named it, ‘Hellfire’). Fakhr al-Din targeted the Latins’ wooden ‘cat-houses’ with volleys of Greek fire to devastating effect. John of Joinville was ordered to man one of these vulnerable towers over a series of nights, and later frankly described the utter terror he and his men experienced, watching flasks of Greek fire hurtling through the darkened sky like ‘dragon[s] flying through the air’, with long ‘tail[s] of fire stream[ing] behind’ them. One day in early 1250 when John was not on duty, the Ayyubid barrage finally told, and the towers went down in flames. Thankful that this had not occurred on his watch, Joinville wrote, ‘I and my knights praised God for such an accident.’40

Even with the ‘cat-houses’, the attempts to fashion a causeway had been failing because the river’s fast-moving current eroded the structure. In the first week of February, Louis called off the futile efforts, and morale within the camp sank as it seemed an impasse had been reached. Around this same time, however, a Muslim traitor–variously described as a Bedouin or as a deserter from the Egyptian army–told the Latins about a ford some distance down the course of the Tanis that would give them access to the southern banks of the river. Offered this unexpected glimpse of hope, the French king immediately decided to use this ford to mount a direct attack on the Ayyubid camp.

Aware of the terrible risks involved in this operation, and of the lethal consequences of being caught and surrounded on the far side of the Tanis, Louis formulated his tactics with care. To avoid detection, the crossing would begin before daybreak. The depth of the ford and the need for swift engagement precluded the involvement of infantry, so only mounted knights and sergeants were selected. And with an eye to maintaining strict discipline, these men were drawn from the king’s trusted French contingents and the Templar and Hospitaller Orders. The Franks of Outremer and the Teutonic Knights were to remain in place, defending the northern camp. Above all, it was imperative that the entire strike force reach the south bank and regroup before any attack was mounted. With this in mind, Louis ‘commanded them all–great men and small–that no one should dare to break ranks’.41

The Battle of Mansourah

Before first light on Tuesday 8 February 1250, the king’s plan was put into action. The Templars led the way, closely followed by a party of knights commanded by Louis’ brother Count Robert of Artois, which included the Englishman William Longsword, earl of Salisbury. It soon became clear that the ford was deeper than expected, requiring horses to swim midstream, and the steep, muddy banks on either side caused some crusaders to fall from their mounts and drown. Nonetheless, hundreds of Franks began to emerge on the far shore.

Then, just as the sun was rising, Robert of Artois made a sudden and unexpected decision to launch an assault, charging at the head of his men towards the Ayyubids’ riverside base. In the confusion, the Templars followed close behind, leaving Louis and the bulk of the strike force stranded in the ford. In this one instant, all hope of an ordered offensive evaporated. It is impossible to know what caused Robert to act so precipitously: perhaps he saw the chance for a surprise attack slipping away; or the promise of glory and renown may have spurred him on. As he rode off, those left behind–the king included–must have felt a mixture of shock, puzzlement and anger.

Even so, at first it looked as though Robert’s audacity might win the day. Ploughing into the unsuspecting Muslim camp, where many were still asleep, the count’s combined force of around 600 crusaders and Templars encountered only token resistance. Racing in among the enemy tents, they began the work of butchery. Fakhr al-Din, who was carrying out his morning ablutions, quickly threw on some clothes, mounted a horse and rode out, unarmed, into the tumult. Set upon by a party of Templars, he was cut down and slain by two mighty sword blows. Elsewhere the slaughter was indiscriminate. One Frankish account described how the Latins were ‘killing all and sparing none’, observing that ‘it was sad indeed to see so many dead bodies and so much blood spilt, except that they were enemies of the Christian faith’.42

This brutal riot overran the Ayyubid encampment and, had Robert now elected to hold the field, reorder his forces and await Louis’ arrival, a stunning victory might well have been at hand. But this was not to be. With Muslim stragglers streaming towards Mansourah, the count of Artois made a woefully hot-headed decision to pursue them. As he moved to initiate a second charge, the Templar commander urged caution, but Robert chided him for his cowardice. According to one Christian account, the Templar replied: ‘Neither I nor my brothers are afraid…but let me tell you that none of us expect to come back, neither you, nor ourselves.’

Together they and their men rode the short distance south to Mansourah and raced into the town. There the folly of their courageous but suicidal decision immediately became apparent. On the open plain, even in the Ayyubid camp, the Christians had been afforded the freedom to manoeuvre and fight in close-knit groups. But once in among the town’s cramped streets and alleyways, that style of warfare proved impossible. Worse still, upon entering Mansourah, the Franks came face to face with the elite Bahriyya regiment quartered in the town. This was to be the Latins’ first deadly encounter with these ‘lions of battle’. A Muslim chronicler described how the mamluks fought with utter ruthlessness and resolve. Surrounding the crusaders ‘on every side’, attacking with spear, sword and bow, they ‘turned their crosses upside down’. Of the 600 or so who rode into Mansourah barely a handful escaped, and both Robert of Artois and William Longsword were killed.43

Back on the banks of the Tanis, as yet unaware of the dreadful slaughter then just beginning in Mansourah, Louis was making a valiant attempt to retain control of his remaining troops, even as squadrons of mounted mamluks began racing forward to counter-attack. One crusader described how ‘a tremendous noise of horns, bugles and drums broke out’ as they drew near; ‘men shouted, horses neighed; it was horrible to see or hear’. But in the thick of the throng, the king held his nerve and slowly fought his way forward to establish a position on the southern edge of the river, opposite the crusader camp. Here the Franks rallied to the Oriflame and made a desperate attempt to hold their ground, while the mamluks loosed ‘dense clouds of bolts and arrows’ and rushed in to engage in hand-to-hand combat. The damage sustained on that day was appalling. One of Joinville’s knights took ‘a lance-thrust between his shoulders, which made so large a wound that the blood poured from his body as if from a bung-hole in a barrel’. Another received a blow from a Muslim sword in the middle of his face that cut ‘through his nose so that it was left dangling over his lips’. He carried on fighting, only to die later of his injuries. As for himself, John wrote: ‘I was only wounded by the enemy’s arrows in five places, though my horse was wounded in fifteen.’