the end of the decade. In Africa, the two great empires were the Christian Ethiopian Empire in the east and the Muslim Mali Empire in the west. Amda Seyon I, who had brought Ethiopia to its height, was succeeded in 1344 by Newaya Krestos, who continued to foster trade in East Africa. Mansa Suleyman assumed office in the Mali Empire in 1341, and similarly took steep measures to reform Mali's finances. Songhai, which had emerged in this decade, was conquered by Mali for the time being. In the Americas, cities of the Mississippian culture such as Cahokia, Kincaid and Moundville went into an accelerated state of decline in this decade. Factors such as depletion of resources, climatic change, war, disease, social unrest and declining political and economic power have been suggested, although the sites were not fully abandoned until the 15th century. Central America saw the decayed Maya civilization ruled from their capital Mayapan in the Yucatán Peninsula, while the Mexicas from their capital city of Tenochtitlan were on the rise. Political leaders Asia Political developments Mongol decline In the Kipchak Khanate, Özbeg Khan of the Golden Horde died in 1341, ending what Muslim chroniclers considered a golden age. His elder son Tinibeg ruled for a year or two, before being dethroned and killed at the hands of his younger brother Janibeg in 1342. Janibeg's fifteen-year reign was notable for the appearance and rapid transmission of the Black Plague along the trade routes from inner Asia in this decade. The nation "struggled into new life" after the plague had passed in the following decade. The Chagatai Khanate was being split by religious dissensions between the traditionalist Mongol adherents of the Yasa and the Mongol and Turkish converts to Islam. The eastern half of Chagatai seceded under the conservative Mongol element when Tughluk Temür seized power in Moghulistan around 1345. The Khanate continued in Transoxiana, but the Chatagai khans became the puppets of the now enthusiastically Muslim Turkish amirs, and the amir Kazghan overthrew the Khan Kazan in 1347. In the Persian Ilkhanate, the Mongol House of Hülegü had been extinguished in the male line with the death of Il-Khan Abu Sa'id in 1335, . As JJ Saunders wrote, "A crowd of competitors for the vacant throne started up, but of some history has scarcely condescended to record their names, much less their actions, and an interval of more than thirty