Bertran de Born was a castellan from the bishopric of Perigord, and he was the lord of a castle called Hautefort. He was at war with his neighbors all the time, with the count of Perigord, and with the viscount of Limoges, and with his brother Constantine, and with Richard as long as he was Count of Poitiers. He was a good knight and a good warrior, and a good lover of ladies, and a good inventor of poetry, and he was wise and eloquent, and he knew well how to deal with good and with evil men. He influenced, whenever he wished, King Henry and his son; but he always wanted them to be at war with one another, one against the other. And he always wanted the King of France and the King of England to be at war with each other. And if they had peace or a truce, he would at once make an effort with his serventes to undo the peace, and to show how each one of them was being dishonored by that peace. Thus he reaped much gain and was lost.
….And Bertran de Born used to boast that he was of such worth that he did not think he would ever need all his wit. And afterwards the King took him prisoner, and after he had imprisoned him, he said to him, “Bertran, you will now need all of your wit.” And Bertran answered that he had lost all his wit when the Young King died. So the king wept for the death of his son and pardoned him and gave him clothing and land and honor. And he lived for a long time in this world and later joined the order of Citeaux. And here you will find some of his sirventes.
Vida #17, quoted from:
Egan, Margarita, The Vidas of the Troubadours, Vol. 6 Series B, Garland Library of Medieval Literature, NY, 1984, pages 17-19.