So he made ready for the feast, and a day was prefixed when they should be wedded. Wherefore Queen Guenever was passing heavy, but she durst not discover her heart, and spake fair, and agreed to Sir Mordred's will. Then she desired of him for to go to London, to buy all manner of things that longed unto the wedding, and because of her fair speech Sir Mordred trusted her well enough, and gave her leave to go. When she came to London, she took the Tower of London, and suddenly, in all haste possible, she stuffed it with all manner of victual, and well garnished it with men, and so kept it.

Then when Sir Mordred wist and understood how he was beguiled, he was passing wroth out of measure. And, a short tale for to make, he went and laid a mighty siege about the Tower of London, and made many great assaults thereat, and threw many great engines unto them, and shot great guns. But all might not prevail Sir Mordred, because Queen Guenever, for fair speech nor for foul, would never trust to come in his hands again.

Then came the Bishop of Canterbury, the which was a noble clerk and an holy man, and thus he said to Sir Mordred: "Sir, what will ye do? Will ye first displease God, and then shame yourself and all knighthood? Leave this matter, or else I shall curse you with book and bell and candle."

"Do thou thy worst," said Sir Mordred; "wit thou well I shall defy thee."

"Sir," said the Bishop, "and wit ye well I shall not fear me to do that I ought to do. Also, when ye noise that my lord Arthur is slain, that is not so, and therefore ye will make a foul work in this land."

"Peace, thou false priest," said Sir Mordred, "for, if thou chafe me any more, I shall make strike off thy head."

So the Bishop departed, and did the curse in the haughtiest wise that might be done. Then Sir Mordred sought the Bishop of Canterbury for to slay him, and he fled, and, taking part of his goods with him, went nigh unto Glastonbury, and there lived in poverty and in holy prayers as priest-hermit in a chapel, for well he understood that mischievous war was at hand.

Then came word to Sir Mordred that King Arthur had raised the siege from Sir Launcelot, and was coming homeward with a great host, to be avenged upon Sir Mordred. Wherefore Sir Mordred made write writs to all the barony of this land, and much people drew to him, for then was the common voice among them, that with Arthur was none other life but war and strife, and with Sir Mordred was great joy and bliss. Thus was Sir Arthur depraved and evil said of, and many there were that King Arthur had made up of naught, and had given lands to, who might not then say of him a good word.

Lo all ye Englishmen, see ye not what a mischief here was, for Arthur was the most king and knight of the world, and most loved the fellowship of noble knights, and by him they were all upholden. Now might not these Englishmen hold us content with him. Lo, thus was the old custom and usage of this land, and men say, that we of this land have not yet lost nor forgotten that custom and usage. Alas, this is a great fault of all Englishmen, for there may no thing please us. And so fared the people at that time; they were better pleased with Sir Mordred than they were with King Arthur, and much people drew unto Sir Mordred, and said they would abide with him for better and for worse.

So Sir Mordred drew with a great host to Dover, for there he heard say that Sir Arthur would arrive, and so he thought to beat his own uncle from his lands. And the most part of all England held with Sir Mordred, the people were so new-fangle.