where he had been proclaimed sultan following his father's death. His arrival was the impetus for a new Egyptian offensive. A squadron of light boats were made and transported by camel to the lower portion of the Nile. There they began to intercept the boats that brought food from Damietta, capturing more than eighty Frankish ships. On 16 March 1250 alone, a convoy of thirty-two were lost at one fell swoop. The Franks were quickly beset by famine and disease, including dysentery and typhoid. The Battle of Fariskur fought on 6 April 1250 would be the decisive defeat of Louis' army. Louis knew that the army must be extricated to Damietta and began negotiations, offering Turanshah the exchange of Damietta for Jerusalem. The Egyptians realized his disadvantageous position and rejected the offer. In planning their retreat, Louis' officers urged him to go immediately to Damietta. He refused to leave his men. It was decided that the sick should be sent by boat down the Nile and the able-bodied should march along the road by which they had come. They departed on the morning of 5 April, and the painful journey began, with the king in the rear and the Egyptians in pursuit. The Franks managed to get across the al-Bahr as-Saghit, but neglected to destroy the pontoon behind them. The Egyptians crossed over and began attacking the Franks from all sides. Their attacks were repulsed and the Franks moved slowly on, with Louis falling ill that night. The next day, the Muslims surrounded the army at the town of Fariskur, 10 miles southwest of Damietta, and attacked in full force. Hugh XI of Lusignan was among the dead. To the sick and weary soldiers, it was clear that the end had come. Geoffrey of Sergines, commander of the royal bodyguard, sheltered the king at nearby Sharamsah. On 6 April, Louis' surrender was negotiated directly with the sultan by Philip of Montfort. The king and his entourage were taken in chains to Mansurah and his whole army was rounded up and led into captivity. The ships conveying the sick to Damietta were surrounded and captured. The Egyptian victory was total. An agonized Templar knight lamented: Louis' captivity and release The Egyptians were surprised by the large number of prisoners taken, estimated by the sultan himself at 30,000, certainly an exaggeration, but likely most of Louis' force. Unable to guard all of