The principle of persecution had, as we saw, been established in the Lateran centuries before, and the only thing that restrained Innocent from applying it, in its bloodless form, was the refusal of the secular rulers to co-operate. Raymond of Toulouse was too healthily Epicurean to favour either the sombre creed of the heretics or the more sombre creed of the persecutor. Apologetic writers speak with horror of the number of his wives and fair friends, but we do not find that his conduct in this regard, or the similar conduct of other princes and prelates, attracted the attention of the Pope. When, however, he slighted a sentence of excommunication and still refused to persecute his excellent but unorthodox subjects, he received a withering letter.[251] "Who does he think he is?" the Pope asks scornfully, to disobey one before whom the greatest monarchs of the earth bow. Let him cease to "feed on corpses like a vulture"--to break a lance with his neighbours--and obey the Legates, or the Pope will invite a more powerful prince to displace him. As early as November 17, 1207, Innocent bade the King of France, the Duke of Burgundy, and other nobles, prepare for an expedition to Toulouse; and the privileges of Crusaders were promised to all who joined it. Raymond was more moved by the political threat than by the spiritual censures, but there was sullen anger amongst his followers, and on January 15, 1208, the Legate Pierre de Castelnau was assassinated. There is not a tittle of evidence to incriminate Raymond, and it is in the highest degree improbable that he would thus open the gates to his greedy neighbours, but Innocent chose to believe that he had directed the murder. Without trial, he declared that Raymond had forfeited the allegiance of his subjects, and his dominions might be seized by any Christian prince. He spurred Philip of France--who must have been flattered to find himself now described as "exalted amongst all others by God"--to the attack.[252] He addressed a fiery summons to "all the nobles and people of France" to "avenge this terrible insult to God."[253] Philip wanted Toulouse, but he overreached himself in making terms and he dreaded England. There were, however, plenty of nobles willing to lead their men to the plunder of prosperous Provence, and the clergy had become seriously alarmed at the spread of the heresy in France. A vast army, joyous at the rich prospect of loot, converged upon the southern State. Innocent III. knew better than we know the forces he had set in motion. The end sanctified the means.