the time. Another account of the events in the Crimea reads: It seemed to the besieged Christians as if arrows were shot out of the sky to strike and humble the pride of the infidels who rapidly died with marks on their bodies and lumps in their joints and several part, followed by putrid fever; all advice and help of the doctors being of no avail. Whereupon the Tartars, worn out by this pestilential disease, and falling on all sides as if thunderstruck, and seeing that they were perishing hopelessly, ordered the corpses to be placed upon their engines and thrown into the city of Kaffa. Accordingly were the bodies of the dead hurled over the walls, so that the Christians were not able to hide or protect themselves from this danger, although they carried away as many dead as possible and threw them into the sea. But soon the whole air became infected, and the water poisoned, and such a pestilence grew up that scarcely one out of a thousand was able to escape. Modern scholars consider this one of the earliest, and most deadly, biological attacks in world history, though in the end the Mongols were forced to retreat. Early sources state that the plague began its spread in the spring of 1346 at the River Don near the Black Sea, then spread throughout Russia, the Caucasus, and the Genovese provinces within the year. Further south in Georgia, King George the Brilliant died and was succeeded by King David IX. King George V had managed to increase the Georgian realm to all of Transcaucasia. However, after 1346 the Kingdom began to decline, caused by George's death and the devastating spread of the plague throughout the area soon afterwards. Central and East Asia Central Asia was marked in 1346 by the continued disintegration of the Mongol's domains, as well as by Muslim expansion. Kazan Khan, emperor of the Chagatai Khanate, was killed by the forces of Qazaghan in this year, putting an end to the Chagtai Khanate's status as a unified empire. Qazghan was the leader of the group of Turkish nobles opposed to Mongol rule. Qazghan had been wounded by Kazan's forces earlier in the year, but rather than taking advantage of his opponent's weakness, Kazan retreated and many of his troops abandoned him. To the east, Kashmir was conquered by Shah Mir, the first Muslim to rule