The Crusaders went out by the Sales Gate. The evidence seems to show that they traversed the chatelet or outwork, and left the fortifications by the eastern gate through which they had entered the town. They then followed the road between the eastern wall and the river, marching all the time with the least possible noise as to avoid attracting attention. Evidently the first part of the movement (i.e., the passage through the outwork) was a feint at retreat deliberately shown to the enemy in order to mislead him, and the second (the march along the river bank) a concealed move, in order to obtain the effect of surprise. The column followed the route by which they had come until the bridge over the Garonne was reached. Then, instead of turning to the right and crossing it, they went straight ahead, passed under the walls of the castle, and (still unobserved by the enemy) crossed the St. Sernin bridge at the mouth of the Louge. As soon as the first squadron had crossed, it deployed to the left and charged down upon those of the enemy (i.e., part of the Toulousain militia reinforced by certain Catalan knights, under the Count of Foix) who had that morning unsuccessfully attacked the Toulouse Gate. William d’Encontre and William des Barres surprised them completely, and scattered them in a few moments, “like dust before a gale.”

The technical phases of this part of the action seem never to have been considered by historians. Inasmuch are they are of some interest in themselves, and furthermore, shed light upon the flagrant indiscipline in the southern army, they are worth a moment’s consideration.

The known elements of the problem are these: first the undisputed facts that the surprise was complete and that the successful charge was made only by some three hundred horsemen; second, the weight of evidence in favour of the route just described as that of the sortie.

The time element involved remains to be computed. The full distance from the Sales Gate, past the town, over the bridge, and up the abrupt ramp leading to the plain, is nearly 700 yards. From the numerous mediæval gates extant, together with the extant brick remains of the northern abutment of the bridge in question, we may be certain that the formation was a column of twos. We may be almost equally certain that the gait was a walk, for (in the first place) it would have been nearly impossible to trot up the final steep ramp, (secondly) silence was desired, and (thirdly) to trot through such a long narrow space would have exposed the cavalry to the risk of a serious snarl in case a single horse fell or behaved badly—in which case the whole operation would have been compromised. Assuming the gait to have been a walk, we are entitled to reduce the distance occupied by each horse to three yards, leaving a bare one foot between nose and crupper. The length of the entire column must therefore have been at least 450 × 3 = 1,350 yards, nearly double the distance to be traversed, and the length of each squadron must have been 450 yards. Before falling out to eat and drink, we may be sure that the Toulousains and Catalans must have retreated at least 150 yards north of the Toulouse Gate in order that so large a target as they would present might be out of long bowshot. Therefore the head of the crusading column would come into full sight practically as soon as it topped the ramp and gained the plain, and historians who assume that the deployment could have been made out of sight of the Toulousains and Catalans have simply never troubled to walk over the battlefield. Assuming a walking gait to be four miles per hour, i.e., 117 yards per minute, the rear of the first crusading squadron would be in the plain almost exactly four minutes after the van had come in sight of the enemy in front of the Toulouse Gate. The greater part of the 600 yards separating the Crusaders from the enemy would almost certainly be covered at a trot of say eight miles an hour, before breaking into a gallop for the final shock. Two minutes, plus the time necessary for deployment, must therefore be added to the original four. In all, nearly ten minutes must have elapsed between the first observation of the Crusaders by Foix’s command and the delivery of the crusading charge.

Inasmuch as Foix’s men far outnumbered the first crusading squadron, the fact that they were unable (when their seven minutes’ grace was up) to make even a few moments effective resistance shows their discipline to have been wretched. We know that they had committed the imprudence of falling out to eat and drink, that most of the Catalan knights had put off their armour, and that no proper measures of security had been taken. Nevertheless, it seems that the Crusaders should at least have been delayed a few moments. Not one of Foix’s Catalan knights was killed!

Meanwhile, the main body of the besiegers was getting to horse, crying “Aragon,” “Foix,” or “Comminges,” according to their allegiance. The Spaniards formed, but the formation was ragged. In part this may have been due to haste, although they must have had over twenty minutes in which to get in line, assuming a minimum of ten minutes from the disclosure of the operation to the deployment of the second crusading squadron, and an additional minimum of ten minutes for the second squadron to catch up with the first and for the two together to do the mile which separated them from Pedro’s people. In part it certainly resulted from the folly and indiscipline of the Spanish knights; every important man among them (so Pedro’s son King Jaime tells us) wanted to fight his own battle with the enemy, making strict alignment and combined action impossible. Furthermore, as we learn from other chronicles, Pedro himself exercised no effective command, but yielded to his chivalric enthusiasm by exchanging armour with one of his knights and posting himself in the front ranks—a piece of generous but unmilitary folly surprising in a soldier of his considerable experience since it lost him all control over his forces in reserve. The Aragonese were facing south astride the Seysses road about a mile out from Muret, with the Pesquies marsh covering their left.

Having broken Foix’s command, the first crusading squadron had to wheel half right in order to strike Pedro. By spurring hard, the second, with a straighter course to follow, was able to catch up, and both together went at the Aragonese, sweeping before them some of Foix’s routed horsemen. Count Simon’s orders on no account to engage in individual jousting but to charge boot to boot were so well obeyed that the shock was simultaneous all along their line. It was so violent that the Crusaders plunged into the horsemen opposed to them “like a stone dropped into the water.” Pedro’s people stood firm and closed round them, hiding them from the third “battle,” and the melée swayed back and forth with a din “as of countless axemen hewing down a forest.”

De Montfort, with the idea of charging in on Pedro’s left, worked rapidly north and east around the marsh until he found himself blocked by Pesquies ravine, which the chroniclers describe as a “fossatum” (i.e., a ditch or trench). Cut in the steep banks of this obstacle was a narrow path, blocked at the farther end by a strong Aragonese combat patrol or covering detachment. Such covering detachments were familiar enough, as we learn from the “Siete Partidas” of Alfonzo the Wise of Castile, written about 1260, in which they are called alas or citaras. If it be objected that Pedro was in no mood to think of such details as posting this detachment, we may fairly imagine some grizzled knight of Aragon who knew enough to take on the job by himself with his own immediate followers.

To go from line to column and try to force the narrow path in the face of opposition was a bad business, but de Montfort had no choice. Time was passing, he had the marsh on his left and the ravine stretching away on his right. At the head of his men he crossed the ravine and set his horse to scramble up the farther bank. In this unfavourable position, as he struggled to protect himself from the blows he could not yet hope to return, he broke his left stirrup leather—the third time one part or another of his equipment had played him false that day. With great dexterity he kept his seat and, reaching the summit of the bank, unhorsed the nearest enemy with a blow of the fist to the jaw—the Spaniard must have been wearing not a closed pot-helm but an open-faced steel cap. This man seems to have been the detachment commander, for when his followers saw him fall they broke up and fled on the instant. Their flight exposed to Count Simon the left flank of the Aragonese main body. He got his three hundred across, deployed them, and charged.

All this time the first two crusading squadrons had been fighting hard. Although their close formation and the fury of their charge had carried them deep into the ranks of their enemies, still these last had not broken, but closed in around them. Strict order and alignment had gone and the fighting was man to man. The knight who had taken the part of Pedro could not equal his master’s prowess, and Pedro himself forgot caution, and cried out: “I am the King.” Whereupon those who had sworn to have his life closed around him and killed him, despite his valor and his skill in arms.