During the Third Crusade, shortly after the death of Frederick Barbarossa (June, 1190), a severe pestilence broke out in the army that was besieging Antioch; according to Michaux only 5,000 infantrymen and 700 cavalrymen survived out of the entire German army.[7] At the siege of Acre (Ptolemais), which lasted from August 1189, to July 1191, there broke out in the winter of 1191 a terrible pestilence which played havoc in the pilgrim army; it was caused by an inadequate supply of food, and its symptoms (enlargement of the limbs and falling out of the teeth) betoken scurvy. It also appeared in the army of Saladin, but was much worse in the Christian army, in which from 100 to 200 crusaders died every day. Duke Frederick of Swabia succumbed to this disease on January 20, 1191.[8] At the time of the crusade against the heretics a serious pestilence broke out in Egypt in the army of the crusaders, which had already, on August 12, 1218, suffered from dysentery; it appeared in December during the siege of Damietta, after a heavy and continuous downfall of rain. ‘The patients’, says Wilken, ‘were suddenly seized with violent pains in the feet and ankles; their gums became swollen, their teeth loose and useless, while their hips and shin bones first turned black and then putrefied. Finally, an easy and peaceful death, like a gentle sleep, put an end to their sufferings. A sixth of the pilgrim army was carried away by this disease, which no medicine could cure.’[9] Only a few patients who survived the winter were helped to recovery by the warmth of spring. It was unquestionably a severe form of scurvy. The besieged, too, suffered from the destructive pestilence, and also from Egyptian ophthalmia. We read further in Wilken: ‘A horrible sight greeted the pilgrims when they took possession of Damietta. Not only the houses, but even the streets were filled with unburied corpses; in the beds dead bodies lay beside helpless and dying invalids, and the infection of the air was intolerable. Of 80,000 inhabitants which the city had had at the beginning of the siege only 3,000 were left, while only 100 of these were healthy.’[10] Other reports say that 10,000 inhabitants survived. In 1270, during the Seventh and last Crusade, which strangely enough passed by way of Tunis, a pestilential disease broke out in Carthage, carrying away, in addition to many soldiers and men of rank, King Louis IX of France himself and his son, Jean Tristan. This pestilence was dysentery, and it spread even to Sicily, whither the king’s body was conveyed. After the king’s death conditions were even worse, since so many people died that it was impossible to bury all the bodies. The disease also attacked the enemy’s army.[11]