In 1536 a fresh dispute for the possession of the Milanese broke out between the King of France and the Emperor. It began with a negotiation, artfully protracted by Charles, who promised the investiture, sometimes to the second, sometimes to the youngest son of his formerly impetuous rival, whom he thus amused, while he took measures to crush him by the weight of his arms. But if misfortune had made the King of France too cautious, prosperity had inspired Charles with a haughty presumption, which gave the semblance of stability to every chimerical vision of pride. In 1536 he attempted the conquest of France by invading Provence; but his designs were frustrated by a conduct so opposite to the national genius of the French, that it induced them to murmur against their general. Charles however felt by experience the prudence of those measures, which sacrificed individual interests to the general good, by making a desert of the whole country. Francis marked his impotent hatred by summoning the Emperor before parliament by the simple name of Charles of Austria, as his vassal for the countries of Artois and Flanders. The charge was the infraction of the treaty of Cambray, the offence was laid as felony, to abide the judgment of the court of peers: on the expiration of the legal term, the two fiefs were decreed to be confiscated. A fresh source of hostility broke out on the death of the young Dauphin of France, who was said to have been poisoned, and the king accused Charles V. of the crime. But there is neither proof nor probability to support the charge: and the accused could have no interest to commit the act imputed to him, since there were two surviving sons still left to Francis.