Legends of Charlemagne by Thomas Bulfinch

Charlemagne was overwhelmed with grief at the loss of so many of his bravest warriors at the disaster of Roncesvalles, and bitterly reproached himself for his credulity in resigning himself so completely to the counsels of the treacherous Count Gan. Yet he soon fell into a similar snare when he suffered his unworthy son, Charlot, to acquire such an influence over him, that he constantly led him into acts of cruelty and injustice that in his right mind he would have scorned to commit. Rinaldo and his brothers, for some slight offence to the imperious young prince, were forced to fly from Paris, and to take shelter in their castle of Montalban; for Charles had publicly said, if he could take them he would hang them all. He sent numbers of his bravest knights to arrest them, but all without success. Either Rinaldo foiled their efforts and sent them back, stripped of their armor and of their glory, or, after meeting and conferring with him, they came back and told the king they could not be his instruments for such a work.

At last Charles himself raised a great army, and went in person to compel the paladin to submit. He ravaged all the country round about Montalban, so that supplies of food should be cut off, and he threatened death to any who should attempt to issue forth, hoping to compel the garrison to submit for want of food.