This virtuous prince, the only man who, in like circumstances, could safely have been entrusted with such an authority by a neighbouring nation, had never ceased to interpose his good offices between the English factions; and had even, during the short interval of peace, invited over to Paris both the king and the Earl of Leicester, in order to adjust the differences between them, but found that the fears and animosities on both sides, as well as the ambition of Leicester, were so violent as to render all his endeavours ineffectual. But when this solemn appeal, ratified by the oaths and subscriptions of the leaders in both factions, was made to his judgment, he was not discouraged from pursuing his honourable purpose. He summoned the states of France at Amiens, and there, in the presence of that assembly, as well as in that of the King of England and Peter de Montfort, Leicester's son, he brought this great cause to a trial and examination. It appeared to him that the provisions of Oxford, even had they not been extorted by force, had they not been so exorbitant in their nature, and subversive of the ancient constitution, were expressly established as a temporary expedient, and could not, without breach of trust, be rendered perpetual by the barons. He therefore annulled those provisions; restored to the king the possession of his castles, and the power of nomination to the great offices; allowed him to retain what foreigners he pleased in the kingdom, and even to confer on them places of great trust and dignity; and, in a word, re-established the royal power on the same footing on which it stood before the meeting of the parliament at Oxford.
But while he suppressed dangerous innovations, and preserved unimpaired the prerogatives of the English crown, he was not negligent of the rights of the people. Besides ordering a general amnesty for all past offences, he declared that his award was not in any way intended to derogate from the liberties enjoyed by the nation in virtue of any concessions or charters from the crown.
The award of Louis may have been just in the abstract, and was certainly in accordance with the principles of the English constitution; but it involved measures which, under present circumstances, it was by no means expedient should be carried into effect. The barons might, indeed, have pressed too heavily upon the royal prerogative, and seized on every side, with little scruple, the securities they considered necessary; but it was certain that if those securities were suddenly and completely relinquished, the national charters would become as wholly inoperative as they were before the parliament of Oxford. The word of the king had ceased to have any weight whatever; and the barons determined to resist the award of Louis, and once more to take up arms. Again the country was desolated by civil war, which was renewed with more than its former fury.
The northern counties and those of the west remained attached to the cause of the king; while the strength of the barons lay in the midland and south-eastern counties, the Cinque Ports, and the neighbourhood of London. The citizens of the capital especially were conspicuous for the firmness with which they supported the barons, and the powerful assistance which they rendered to the insurgent cause. At the opening of the campaign various successes attended the movements of the royal troops. Elated by his good fortune, Henry marched to the south with the view of gaining the adhesion of the Cinque Ports. Meanwhile Leicester had remained in London; and thence, while watching the successful career of the king, had employed himself, with the calmness of a skilful general, in concentrating a body of forces. Having accomplished this object, he marched from the capital, determined to meet the king in the south, and compel him to a decisive battle. The army of Henry was greatly superior in numbers to the force marching against him, and therefore he resolved to await his enemies in the spot where he was already encamped—in a hollow or valley at Lewes, in Sussex. Leicester marched his troops to the downs about two miles from Lewes, where he encamped for the night.
The interval of repose was not suffered to pass unimproved. Leicester employed it in arousing in his favour all the superstitious feelings of his soldiery. In time of war or peace he had always been noted for his strict observance of religious forms; and he compared his own life and the cause in which he was engaged with the perjuries and treacheries of Henry, which he said had withdrawn from that king all favour of Heaven. He commanded that his army should wear a white cross, in token that they were engaged in a sacred war; and the Bishop of Chichester, one of his associates, gave a solemn absolution to the troops, promising honour to those who lived, and to those who fell the welcome of martyrs in heaven.
The evening hours were thus spent in exciting to the utmost the enthusiasm of the troops. On the morning of the 14th of May (1264), the earl prepared for the attack, and, leaving a reserve behind him, he descended upon the royal forces. On the king's side were the barons whose names have been already mentioned, together with John Baliol, Robert Bruce, and John Comyn from beyond the Scottish border. On the side of Leicester were the Earls Gloucester and Derby, Robert de Roos, John Fitz-John, John de Vescy, Nicholas Seagrave, Richard Grey, William Marmion, and many other powerful nobles.
As the two armies joined battle, the attack was commenced by Prince Edward, who on this day displayed evidence of that military talent and gallantry which were afterwards to become so conspicuous. The prince led a body of troops upon a force of Londoners, who had armed themselves in the cause they supported. Unskilled in the art of war, and probably much inferior in their appointments, the citizens gave way before the heavy cavalry of Edward, which cut them to pieces. The prince remembered the insults they had offered to his mother, and in his eagerness for vengeance he pursued the flying Londoners, perfectly regardless of what might happen to the rest of the royal army. Leicester meanwhile took advantage of this impetuosity and, collecting his forces into a compact and dense mass, led them against the main body of the king's troops, and completely defeated them. Henry himself was taken prisoner, with his brother the King of the Romans, Robert Bruce, and John Comyn.
When the prince returned from the pursuit on which he was engaged, he perceived the fatal error he had committed. The ground was covered with the bodies of his friends, and he learnt from a few breathless fugitives that his father, with many of his chief nobles, was in the hands of Leicester, and that they were all shut up in the priory of Lewes. Scarcely had the Prince received this news when he was attacked by a troop of cavalry, and was compelled to surrender. The Earl Warrenne, and with him the king's half-brothers, escaped from the field, and reached the Continent. It is stated that in this battle 5,000 Englishmen were slain by the hands of their countrymen.
On the following morning a treaty, called the "Mise of Lewes," was entered into between the defeated king and his barons. It was arranged that Prince Edward and Henry, the son of the King of the Romans, should remain in the hands of Leicester as hostages for their fathers, and that another attempt should be made finally to arrange matters by arbitration. The earl, however, who now found himself possessed of almost unlimited power, refused to release the king and his brother, and kept them, as well as their sons, in imprisonment. In this course of action he was supported by the people and by a large majority of the ecclesiastics; and when the Pope issued sentence of excommunication against Leicester and his party, many of the clergy defied the papal authority, and still held up to the admiration of their hearers the man who had been placed under the ban of Rome. They described him as the reformer of abuses, the protector of the oppressed, the avenger of the Church, and the father of the poor.
The popularity which Leicester at this time enjoyed was unexampled; and here we see again the not unfrequent spectacle of a man, strong in the affections of the people, becoming much more a king than he who wears the crown. The earl exercised his authority upon all those barons who still adhered to the royal cause, and compelled them to quit their strongholds, to give up their possessions, and submit to a trial by their peers. In the judgments passed upon these men we see the rapid advance which had lately taken place in civilisation. There were no sentences to death, or abominable torture, or chains; and in most cases the punishment inflicted consisted of a short exile to Ireland. The king's name was still employed in all acts of government, and his captivity was rendered as light as was consistent with the safe custody of his person. Every indulgence, together with all outward demonstrations of respect, was accorded to him, and a similar mildness was evinced towards the other royal prisoners.