The Count of La Marche began the contest. He had powerful allies, but the chief of them, his stepson, Henry III. of England, and his neighbour, Raimond III. Count of Toulouse, were tardy in their movements. Provoked by the devastations committed on his lands, Louis suddenly took the field. He had made great preparations, had provided large stores of provisions, means of transport and encampment, and machinery for carrying on a siege. Four thousand knights and twenty thousand men-at-arms followed him. The provincial militia joined: in short, as it neared the enemy's country, the King's army swelled apace, says the old chronicler, 'like rivers when they approach the sea.' Many fortresses in La Saintonge and L'Angoumois were carried by assault. Furious and desperate with her ill success, the Countess Isabelle of La Marche tried another form of warfare: she gave two of her serfs a poison which they undertook to mix either with the food or wine of the King and his brothers. But when they reached the royal camp, the two poor wretches were discovered, taken, and hanged.
At length the King of England landed at Royan, at the mouth of the Gironde. His Parliament, disliking this war, had refused him any assistance in it; but he brought with him seven of his principal vassals, three hundred knights, and, above all, the treasure which he had succeeded in amassing: 'thirty hogsheads full of esterlings,' says Matthew Paris, 'enough to pay a whole army of Poitevins and Gascons.'
A truce had subsisted for some time between France and England. Henry sent messengers to Louis, informing him that this truce was now broken, since he considered it his duty to defend his step-father, the Count of La Marche, by force of arms. Louis replied, that on his part he had scrupulously respected the truce, and had no thought of breaking it; but that he considered himself quite at liberty to punish a rebellious vassal. So the war began with ardour on both sides; and this young king, docile son of so capable a mother, soon showed himself to be an unsuspected hero.
Near two towns in Saintonge, Taillebourg and Saintes, on a bridge which commanded the approach to the one and before the walls of the other, Louis fought two battles, where his brilliant personal valour and the enthusiastic devotion of his troops decided the victory and caused the surrender of both places.
'At sight of the numerous banners above which the Oriflamme was floating in front of Taillebourg, and of the multitude of tents pitched close together so as to look like one great populous city, Henry III. turned quickly round to the Count of La Marche. "My father," said he, "is that what you promised me? Is this the countless army which you engaged yourself to raise for me; while my sole care should be to provide the money?" "I never said that," replied the Count. "Yea, truly," observed the Earl Richard of Cornwall, brother of Henry III. "I have in my possession a letter in your own hand upon this point." And when the Count of La Marche energetically denied having either signed or sent such a letter, the English king reminded him with some bitterness of his many messages and anxious solicitations for help. "I swear these were never with my knowledge," said the Count. "Blame your mother, who is my wife. Par la gorge de Dieu, it has all been managed without my knowledge."'
Henry III. was not alone in his disgust at the war into which his mother had thus drawn him. The greater part of his English knights quitted him, and asked of Louis permission to travel home to England through France. Some persons about the court objected to this. 'Let them depart,' said Louis. 'I only wish I could get rid of all my foes thus peacefully.' And when he heard his courtiers making a mock of Henry III. who, deserted by the English and pillaged by the Gascons, had taken refuge in Bordeaux, 'Cease,' said he. 'I forbid you either to ridicule him, or to cause him to hate me for your folly. His charity and piety will save him from all danger and all disgrace.'
When the Count of La Marche himself begged for peace, it was granted by the King with all the prudence of a far-seeing politician, and the pitying kindliness of a Christian. He only exacted that the conquered lands should remain the property of the Crown, and, under the suzerainty of the Crown, should belong to the Count of Poitiers; and that with regard to the rest of his estates, the Count of La Marche, his wife, and children should come and ask them as a grant from the mere will of the King. To this the Count added, as a pledge of his future fidelity, that he would maintain in three of his castles a royal garrison at his own expense.
His submission being thus fully made, the Count was brought into the presence of the King with his wife and children, 'where' (it is chronicled) 'they fell upon their knees and broke into sobs and tears, and began to cry aloud, "Most courteous sire, take away thy anger and displeasure from us, and have pity on us, for we have sinned grievously and haughtily against thee. Sire, according to the multitude of thy great mercies, pardon us our misdeeds!" At which the King, who could not contain himself at the sight, bade them rise, and forgave the Count frankly all the evil he had done.'