North African piracy. The proposal by the doge was presented as a crusade. As such it would give prestige to its participants, a moratorium on their debts, immunity from lawsuits, and papal indulgence. The French force, consisting of 1,500 knights under the leadership of Louis II, Duke of Bourbon, lay siege to Mahdia in Tunis. The French were unfamiliar with the terrain, lacked heavy siege equipment, underestimated, and became embroiled in internal quarrels. The Berbers realized that they could not overcome the heavier armed invaders. Tired of the oppressive heat and concerned about the upcoming winter, the French agreed to a treaty negotiated by the Genoese. It is likely that Béthencourt heard stories regarding the Canary Islands from the Genoese, and of the presence of orchil, a lichen used to make a rare and expensive dye. Here too, he again met up with Gadifer de la Salle, whom he had known previously during service under the Duke of Orleans, and who would accompany him to the Canaries. Expedition to the Canary Islands At that time the Canary Islands were mainly frequented by Spanish merchants. To finance his expedition he sold his house in Paris valued at 200 gold francs and some other small pieces of property in December 1401. His cousin, Robert de Bracquemont, French ambassador to Castile, loaned him 7,000 pounds against a mortgage of Bethencourt's estate. According to Moreri, King Henry III of Castile entrusted the conquest of the Canaries to Braquemont who gave the commission to Béthencourt. Béthencourt set sail from La Rochelle on 1 May 1402 with 280 men, mostly Gascon and Norman adventurers, including two Franciscan priests (Pierre Bontier and Jean le Verrier who narrated the expedition in Le Canarien), two Guanches who had been captured in an earlier Castilian expedition and were already baptised, and Jean Arriete Prud'homme who would assist in the conquest as a key adviser and administrator. After passing Cape Finisterre, they put into Cadiz, where he found some of his sailors so frightened that they refused to continue the voyage. Of the eighty crew with which he set out, Béthencourt sailed with fifty-three. He arrived at Lanzarote, the northernmost inhabited island. While Gadifer de la Salle explored the archipelago, Béthencourt left for Cádiz, where he acquired reinforcements at the Castilian court. At this time a power struggle had broken out on the island between Gadifer and Berthin de Berneval, another